According to sources close to the situation, AOL has been busy selecting the board for the company, which is still set to spin itself off by year’s end–even as it slows down a decision on a new search deal with either current partner Google or a more emboldened Microsoft.

AOL is using Spencer Stuart in the search for directors, led by well-known headhunter Jim Citrin, sources said, and the company has already settled on several outside candidates.

The final board is likely to have about 10 members, and up to a dozen.

At least one of those seats will go to CEO Tim Armstrong, with one or two more claimed by its current corporate owner, Time Warner (TWX).

AOL and Time Warner made their own wish list of potential directors earlier this year, but some people are also lobbying the company to join the board.

BoomTown is working on discovering all those names, but sources added that the candidates being looked at are a mix of personalities culled from the media, advertising and Web worlds.

Among the key attributes: More presumably fast-forward and innovative Silicon Valley types that can help burnish AOL’s tarnished tech cred.

Here are some of my picks:

Facebook COO Sheryl Sandberg, Guitar Hero CEO Dan Rosensweig, WordPress founder Matt Mullenweg (actually, AOL should buy the start-up), eBay (EBAY) CEO John Donahoe, LinkedIn Chairman Reid Hoffman or CEO Jeff Weiner, Juniper Networks (JNPR) CEO Kevin Johnson, Netflix (NFLX) CEO Reed Hastings, and former AOL iconic exec Ted Leonsis.

And, just for fun, News Corp. (NWS) digital don (and ousted former AOL head) Jon Miller or former Yahoo President Sue Decker.

(I might also add former AOL exec, Netscape co-founder and all-around entrepreneur Marc Andreessen, but if he joins another tech/Web board, he is going to get splinters.)

That’s because Armstrong has set a strategy centered around the turbocharging of online content, powered by a more flexible platform and paid for by goosing AOL’s graphical advertising business.

This puts the online icon–once a powerhouse and now not so much, having operated inside Time Warner since its merger early in this decade–in more serious competition with Yahoo (YHOO).

Yahoo now dominates content on the Web, with powerful news, sports and finance sites, and has recently been trying to reinvigorate its brand. This week, it launched a new marketing campaign with the motto, “It’s Y!ou.”

Yahoo also recently struck a search technology and advertising partnership with Microsoft (MSFT), which has now aimed its efforts at AOL.

According to sources, Microsoft execs have been aggressively courting AOL to switch its search business from Google (GOOG).

The search behemoth has long been AOL’s partner in what sources at both companies said has been a productive and lucrative relationship.

Armstrong is also a former top exec at Google, which many at the company hope will further cement its chances.

And while the renewal of that deal does not officially need to be struck until late next year, sources add that Google has already prepared and offered what it considers an attractive new deal for AOL.

But, much to Google’s chagrin, with a focus on the spinoff and preparations for some more cost-cutting in the months ahead, AOL has decided not to accept it yet and is not likely to anytime soon.

While hedging the situation in a recent video interview with MediaMemo’s Peter Kafka, Armstrong has also recently met with Microsoft execs, sources said, who have discussed a number of partnership options with him, including a tighter relationship with its MSN content properties.

“There’s no need to rush, especially since there is already a lot on AOL’s plate,” said one source close to the situation. “And, since it has options, AOL is going to take time considering them.”

(For more on Armstrong’s thinking, here’s a link to another video interview I did with Armstrong while both of us were in Germany today, in which he talked about the ad market and AOL’s strategy, but was cagey about being more specific.)

Please see this disclosure related to me and Google.

In BoomTown’s ongoing series, “Microsofties on Parade,” I spent some time earlier this week with Stephen Elop (pictured here), president of Microsoft’s Business division.

Reporting directly to CEO Steve Ballmer, Elop is a newbie, having gotten to Microsoft (MSFT) only a year ago.

Which is why he is enthusiastic in his determination to tell the world that the software giant has gotten the open religion and is becoming “the most interoperable company in the world.”

Elop said that humdinger earlier this week, when he was in San Francisco for an onstage Q&A with Tim O’Reilly at the Web 2.0 Expo.

The statement was met by a show of “no” hands, after O’Reilly asked who in the audience thought that was true.

Still, Elop pressed on, also hinting that Microsoft’s Office products–Excel, PowerPoint, Word–could even be coming to the Apple (AAPL) iPhone.

“Not yet, keep watching,” said Elop, whose portfolio has purview over Office, as well as the Dynamics business applications division and Unified Communications products.

I suppose Elop can be that cheeky, after a lot of Silicon Valley experience as COO of Juniper Networks (JNPR) and CEO of Macromedia, which was acquired under his tenure by Adobe (ADBE).

Or, it could be that he knows from having five kids–including triplet 10-year-olds–that patience is a virtue and that there might be a day when more hands might shoot up.

In any case, here is a video interview I did with Elop, where he talks about making Microsoft a more open and innovative place, the changing business model of software and more:

[UPDATED: H-P exec Todd Bradley has been a public company CEO, which I reflected below correctly.]

With Yahoo board Chairman Roy Bostock reportedly assuring investors and others that the company will have a CEO in place by the end of the year, it seems prudent for BoomTown to initiate an official Yahoo CEO Countdown.

After all, this column had a 100-Day No-Sacred-Cows Vision Quest to mark the time that Jerry Yang said he needed to give Yahoo a top-to-bottom look-see when he took over last summer as CEO.

Yang announced he was stepping down on Nov. 17, prompting the search for someone to lead Yahoo (YHOO) to the promised land where BoomTown countdowns are illegal.

But that’s not today, so here’s the 26-days-to-go update:

It looks like Yahoo has almost no chance to nab a top candidate, News Corp. (NWS) COO Peter Chernin. While Yang made nice and Bostock quickly lobbed in a call to get the well-known exec to come in and talk, several sources said Chernin declined even that.

Of course, moguls like Chernin are pros at not interviewing–one media player schooled me that you apparently never show interest in a job and only take it if a full offer is made, because if you don’t get it after chit-chatting, you look like a loser.

But I don’t think it is a slick feint on his part, even though Chernin is now engaged in contract renewal negotiations at News Corp. (which owns this Web site).

Consider: If you were Chernin, would you want to trade your powerful, well-paid, glamorous job in Hollywood and New York for what will surely be a slog of a job in Sunnyvale, and in a cubicle?

And Chernin has told many he is not interested in doing the job, although News Corp. would still love to do some sort of deal to combine its online assets, like MySpace, with Yahoo’s, as it almost did many times.

While Chernin did just take delivery on a Tesla, showing some clear geekiness, and he would be an exciting get for Yahoo, it’s the longest of shots.

The same is true for some other names that have been floated (by me!).

But several of the people are on the Yahoo board’s list too. And while things can change, it is more unlikely any of them will be the pick.

That includes former Yahoo COO Dan Rosensweig, who has a good life now as a media investor; former eBay exec and OpenTable CEO Jeff Jordan, who told his investors he does not want to be in the running and was sticking with the start-up’s IPO plans–if and when the economy recovers (although Yahoo could buy OpenTable and, thus, Jordan); former eBay (EBAY) CEO Meg Whitman, who could be running for governor of California; and former AOL CEO Jon Miller, who is not secretly buying Yahoo, but who could not be its leader anyway, since he is bound by a Time Warner (TWX) noncompete agreement until the end of March.

Another sticking point: The Yahoo board has limited the pool by a list of six criteria that it has drawn up, with the No. 1 being a CEO candidate has to have public company CEO experience.

If enforced, that nixes some folks, like Google (GOOG) exec Tim Armstrong. In addition, Yahoo President Sue Decker getting the nod is even more unlikely, for that and other reasons, according to many.

From my lists, that leaves DoubleClick head David Rosenblatt (his company is now owned by Google); Demand Media’s Richard Rosenblatt; former Viacom (VIA) head Tom Freston; former CNET CEO Shelby Bonnie; Hewlett-Packard (HPQ) exec Todd Bradley; and Juniper Networks (JNPR) CEO Kevin Johnson, who was the Microsoft exec who was key in the Yahoo takeover attempt there.

All have reasons not to either want or be able to take the Yahoo CEO job, so that means there could be a dark horse candidate. (I am now drawing up yet another list of qualified public CEO tech and media execs).

Here’s one: Yesterday, after it was announced he was stepping down from Microsoft (MSFT) in the wake of its hire of former Yahoo tech star Qi Lu as its online leader, I noted that I liked Brian McAndrews for the job.

Plus, the former CEO of aQuantive, which Microsoft bought for $6 billion last year, would be a delicious irony. But those who have talked to him told me McAndrews–who did want the digital head job at Microsoft and was left hanging by the software giant’s CEO Steve Ballmer–seems intent on taking time off now.

Alternatively, one of the two Yahoo board members, Maggie Wilderotter or John Chapple, both have the public company CEO checked off.

Personally, I am betting on one of them as CEO, although I believe it would be better if Yahoo picked a fresh outside choice.

So do a lot of execs remaining at Yahoo, most of whom visibly roll their eyes at the idea of a board member taking over, considering the record of the directors so far in guiding Yahoo’s fortunes.

That’s why the board–which definitely has not distinguished itself by any criteria so far in Yahoo’s long fall from grace–should try to get it right this time, as Yahoo can’t take any more of the way it has been running the show so far.

BoomTown might have been remiss in my post yesterday on top candidates for the Yahoo CEO job, after the news Monday that Jerry Yang is stepping down, by leaving out several key possibilities.

Yesterday’s roster included News Corp.’s Peter Chernin, Google’s Tim Armstrong, Kevin Johnson of Juniper Networks (JNPR) and also two Yahoo board members, among others. (The main internal candidate, Yahoo President Sue Decker, seems unlikely to get the nod.)

So here is an addendum to my initial list–all of whom are Yahoo (YHOO) outsiders.

Tom Freston:

Chernin is not the only media mogul whose name is being bandied about–the other prominent one is former Viacom head Tom Freston.

Freston apparently got shafted by the–let’s be polite here–disturbingly volatile founder of Viacom (VIA), Sumner Redstone, for not buying MySpace. In fact, News Corp. (NWS), which also owns this Web site, did. But Freston remains a well-respected and creative exec and has been dabbling in the Internet space since leaving Viacom.

Also, Oprah and Arianna love Freston–which is all I need to know.

Jeff Jordan:

Jeff Jordan, the former top eBay (EBAY) exec who is now the CEO of OpenTable, was also on the short list for COO at Facebook, a job that went to former Google exec Sheryl Sandberg.

While the restaurant reservations Web start-up has been headed for a public offering, that event has obviously been pushed out indefinitely by the econalypse, which might be just the impetus to convince Jordan that bussing tables all day is too dull.

Some speculate that Yahoo could buy OpenTable and get Jordan in the process.

Richard Rosenblatt:

Another interesting idea is Richard Rosenblatt of Demand Media, a company that Yahoo was sniffing around not too long ago.

The network of social-networking sites and apps maker is an innovative play in the space and might give Yahoo some much needed Web 2.0 DNA. Demand could still be bought by Yahoo, in order to put Rosenblatt into place.

(Rosenblatt, for those who do not remember, ran the company that owned MySpace, and he was key to selling it to News Corp.)

Also, Lance Armstrong likes Rosenblatt.

Shelby Bonnie:

A reader actually made the excellent suggestion of former CNET head Shelby Bonnie, who is now investing in start-ups. Bonnie is another steady exec–despite leaving CNET, now owned by CBS (CBS), under an options backdating controversy–and is well-liked in the Internet industry.

Yahoo would be a much bigger job than he has ever held, although he certainly has both tech and advertising experience online.

David Rosenblatt:

Lastly, especially if Yahoo is interested in an exec who has turnaround talent, there is probably no better a choice than DoubleClick CEO David Rosenblatt. An experienced online advertising exec, he is also sharply outspoken and knows how to get companies in line and fast.

He is also impossibly rich after Google (GOOG) bought DoubleClick out from under–wait for it–Yahoo recently. While he is still running the show for Google, after having decided to stay, Yahoo might present an interesting challenge for the very savvy Rosenblatt.

Please see this disclosure related to me and Google.

And, no surprise, he is the No. 1 choice of most inside and outside Yahoo (YHOO) in the wake of the news late yesterday that current CEO and Co-Founder Jerry Yang is stepping down.

And why not? Chernin has the right resume: Experienced at running large and complex organizations; savvier than most in media about the Internet; able to make the kinds of dramatic decisions needed; and, perhaps best of all, signaling–via the Los Angeles Times–just this past week that he was open to leaving the powerful media and entertainment conglomerate for something new.

Well, Yahoo would certainly be new for Chernin, in terms of a corporate cleanup challenge, especially compared to figuring out how to make bank on plush toys from “The Simpsons.”

And, while the risks are many, if Chernin (pictured here) managed to turn around Yahoo, he could make a huge fortune too, given Yahoo shares have languished of late, much in the same way they did when former CEO Terry Semel came to Yahoo from Hollywood in 2001.

But it’s not altogether clear whether Chernin would actually leave his powerful perch at News Corp. (NWS)–which owns Dow Jones and owns this Web site. He has been ensconced there for a dozen years, building a huge reputation as a sharp exec (No, Peter, I am not kissing up, as I think Yahoo would wear even you down very, very quickly).

That’s even though many note he is not likely to take over as CEO from its iconic leader, Rupert Murdoch. The media mogul is widely expected to favor one of his own children to lead News Corp. next.

And the 57-year-old Chernin already makes close to $30 million in his current job, which is definitely challenging.

And, although Chernin has been involved in the News Corp.-owned MySpace and has had success backing the Hulu online video site, it is not nearly as hard as the five-year turnaround quagmire (plus no fabulous media mogul perks either) that Yahoo could turn out to be.

In addition, privately to other News Corp. execs, Chernin has regularly pooh-poohed a move to a digital company, even though he is always on the short list for a lot of big Internet jobs–such as the long-unfilled post as digital head at Microsoft (MSFT) more recently.

So, who else to take over from Yang, who will return to his job as Chief Yahoo after stepping down from the company as soon a search for a replacement CEO is successful?

Well, here is BoomTown’s own shortish list, based on asking a wide range of people inside and outside Yahoo, all of whom are important digital players in their own right.

INSIDE YAHOO

Sue Decker:

The current President of Yahoo is certainly being “considered” for the job, which is a polite term for not really being considered at all. While Decker is an intelligent and thoughtful exec, like a politician with a record, she has had her hand on the operating tiller at Yahoo for too long not to get deservedly blamed for its current situation.

In addition, she is radioactive to big investors, who have told the Yahoo board in no uncertain terms that she is a nonstarter.

Maggie Wilderotter:

The former Microsoft exec, who has also been a public company CEO, is an interesting idea floated by some, who think the Yahoo board might turn to one of its own directors, as a short-term solution to stabilize Yahoo.

Wilderotter has been much focused, said several Yahoo execs, on cost-cutting at Yahoo and certainly is not as tarnished, being a more current board member. But she is a largely unknown quantity in the Internet space and, most importantly, at Yahoo.

John Chapple:

The former CEO of Nextel is one of the two board members (former media Frank Biondi Jr. is the other) recently picked by Carl Icahn, when the activist shareholder was admitted on the board as part of the proxy fight settlement.

Chapple has, sources said, been conducting chats with Yahoo execs lately, perhaps as a way to get a lay of the land. If he got the job, it would be clear Icahn had won his Pyrrhic victory (and personal financial defeat) against Yang.

OUTSIDE YAHOO

Dan Rosensweig:

The very funny, but brash, former Yahoo COO is definitely a favorite within Yahoo’s ranks, except for those who don’t like him. But it’s clear Rosensweig does know and love Yahoo, is close to Yang and, ironically, enjoys a tight relationship with Microsoft CEO Steve Ballmer, who also wanted him for the digital head job.

Also, Rosensweig, who does have operating chops, has gotten some much needed time away from Yahoo, as a partner at the tony media investment firm, the Quadrangle Group.

Meg Whitman:

Another dreamy CEO choice, except she has already been a big company CEO at eBay (EBAY), has proved her mettle in building it to a powerhouse–despite the online auction site’s currently harder times–and has the giant fortune to prove it.

And, oh yes, she is likely to be using that pile of cash to run for governor of California, on the Republican ticket.

Jon Miller/Ross Levinsohn:

The Bobbsey Twins of the Internet, the pair are now having a very good time running their own investment company, the Velocity Group.

But, aside from some questioning whether he can make the quick decisions needed at Yahoo, Miller (pictured here on the right), the former head of AOL, does not want to leave his New York home and cannot take any job anyway until his noncompete with Time Warner (TWX) runs out in March.

And former Fox Interactive Media head Levinsohn likes Los Angeles, and probably is too fast a personality for Yahoo (his going there would be a shock to its system, but would be endlessly entertaining to me personally).

Tim Armstrong:

The top ad exec at Google (GOOG) certainly is an interesting idea, although has little of the product experience needed to run Yahoo. But he is a well-respected advertising figure–where Yahoo needs to shine–and could do well with a lot of strong execs under him.

He is also not on a CEO path at Google–paging, Larry Page!–and could be interested in proving he could run a company on his own.

Kevin Johnson:

The former Microsoft exec was supposed to be running Yahoo, if he and Ballmer pulled off their takeover attempt earlier this year. They did not, and Johnson then left Microsoft to run Juniper Networks (JNPR) in Silicon Valley, right up the road from Yahoo, in fact.

But Johnson is likely subject to a noncompete by Microsoft and a strong contract at Juniper too. Still, a very sharp exec, he definitely has the operating, political, technological and digital skills to take on Yahoo. Also, ironically, he and Yang really get along well and like each other, despite the takeover battle.

Of course, there are a lot of other ideas: Disney (DIS) online exec Steve Wadsworth; the outside-the-box choice of former Procter & Gamble (PG) marketing wizard Jim Stengel; Microsoft digital exec Yusuf Mehdi; CBS (CBS) digital head Quincy Smith (whose hyperactive dealmaking would likely lead to a mutant merger between CBS and Yahoo); and former Cisco (CSCO) and current Joost CEO Mike Volpi.

Please post suggestions below or, better yet, send tips to me at here.

Please see this disclosure related to me and Google.

Yahoo CEO Jerry Yang will step down from his job as CEO as soon as the board finds a replacement for him, in what sources close to the situation call a joint decision by him and the company’s directors.

Yahoo (YHOO) will announce the move within the next hour. [UPDATED: Yahoo confirms the move in its official press release.]

But, in a memo to Yahoo’s employees, obtained by BoomTown, Yang confirmed the pending departure, writing: “…we believe the time is now right to transition to a new ceo who can take the company to the next level.”

Yahoo has hired Heidrick & Struggles, the well-known executive search firm, to evaluate candidates, both internally and externally.

After a replacement is found, which the company hopes will be quickly, sources said, Yang will resume his former title as Chief Yahoo and will also remain on the Yahoo board.

While did-he-walk-or-was-he-pushed speculation will no doubt run rampant, sources said Yang already has and will play an important role in the search for his replacement.

Sources close to the board expect the choice will end up being an outsider and is not likely to be current Yahoo President Sue Decker, although she is being considered for the job.

But both she and Yang have been closely affiliated with each other as the company has struggled to right itself after a tumultuous year and its stock price has plummeted.

Yahoo shares closed today at $10.63 after trading at historic lows for a while and giving the company a valuation of only $14.7 billion.

While Yahoo’s board has some execs in mind to become CEO, obvious candidates include News Corp. (NWS) COO Peter Chernin, as well as former AOL head Jon Miller, former eBay (EBAY) CEO Meg Whitman, Google (GOOG) ad exec Tim Armstrong, former Fox Interactive exec Ross Levinsohn and former Yahoo COO Dan Rosensweig (who is currently with the Quadrangle Group).

BoomTown would also throw in former Microsoft top exec Kevin Johnson, now CEO of Juniper Networks (JNPR), and who led the software giant’s abandoned takeover bid against Yahoo earlier this year.

According to sources, both Yang and the board have been discussing the move for months, although Yang has been saying quite explicitly in public that he was going to stay in place to see through the many changes he has made in his 16-month tenure.

In a recent interview with me, in fact, Yang said about his determination to lead:

“In this uncertain environment, I think I am absolutely the right person. Times like this require a leader who really understands this company and its customers, and I think I do. The world is a different place today than even a month ago and I think I am the best person to guide Yahoo through this volatile time.”

In fact, it has always been a volatile time for Yang at Yahoo. He took over suddenly last June from former CEO Terry Semel, whose departure also came after Yahoo’s struggles became increasingly apparent.

Things only got worse for Yang, due to both his own and previous management missteps and also massive external forces, including a hostile takeover attempt by Microsoft (MSFT), which was soon followed by a proxy fight by activist shareholder Carl Icahn.

The Microsoft bid–which was $31 a share–was abandoned, and Icahn dropped the proxy fight, with Icahn joining the board with two other directors he had handpicked.

And while Microsoft has been interested in a deal related to Yahoo’s search business, its CEO, Steve Ballmer, has categorically ruled out a renewed bid.

Yahoo also saw its search business decline in the face of dominance in the market by Google (GOOG), which had ironically started its then-nascent business on Yahoo as its search partner.

Worse still, Yahoo’s strong graphical ad business has suffered badly in the midst of the current economic meltdown.

There has also been an exodus of major executives over the last year, along with recently announced layoffs of 10 percent of the company, which are set to take place Dec. 10.

In addition, Yahoo’s controversial search ad deal with Google collapsed and its talks to merge with Time Warner (TWX) online unit AOL have dragged on.

With all this, sources close to the company said that both Yang and the board felt the company needed another leader to take it to the next level and complete the turnaround efforts Yang has been trying to pull off.

“It was time for someone else,” said one source close to the board.

More, obviously, to come…

Please see this disclosure related to me and Google.

But there is a movement afoot among its developers and other execs at Microsoft (MSFT) to push for Chief Software Architect Ray Ozzie (pictured here), who replaced Founder Bill Gates in the job just over two years ago.

Ozzie’s role at Microsoft has been to think the big thoughts about where computing is going, and he has been integral to the company’s vision of providing “software plus services.”

Essentially, that boils down to Internet-accessed software–which is Microsoft’s longtime cash cow–a kind of mash-up that plays to the company’s strengths.

But some think there is no bigger puzzle for Microsoft to finally solve now than to figure out how to finally succeed in the online space.

Microsoft’s online unit lost $1.2 billion in the past fiscal year, double what it lost in 2007, with quarter after quarter of disappointment, even as rival Google (GOOG) and Microsoft’s acquisition quarry Yahoo (YHOO) have raked in the profits.

That’s why some think Ballmer should put Ozzie in charge. With a long history of being a strong product exec, he also is a well-respected leader throughout Microsoft and, perhaps more importantly, the tech industry.

“We need a real star to shake up the status quo,” said one Microsoft employee, in a sentiment voiced by many BoomTown spoke to. “Ballmer has to put someone who can command the attention and respect of all the parts of Microsoft, which just can’t seem to get it together in our online business.”

But Ballmer (pictured here), said other sources, might be loathe to remove Ozzie from his overall tech guru role and place him in such a grinding and potentially thankless job.

There are other internal candidates at Microsoft for the opening, which was just created after the sudden departure of Platforms and Services Division President Kevin Johnson earlier this week.

With Johnson’s departure, Microsoft announced it would break up the unit into two parts. One will be a Windows/ Windows Live group, headed by Ballmer and run by a trio of execs, and the other will include online services such as search, MSN and online advertising.

There are several insiders quite interested in taking on that daunting task, said sources.

They include Senior Vice President Brian McAndrews, who runs Microsoft’s Advertising and Publisher Solutions Group and who came to the company via its $6 billion acquisition of ad firm aQuantive. He is widely seen at Microsoft as having the leading edge for the position.

Strategic Partnerships SVP Yusuf Mehdi, who has run online businesses for Microsoft before, is also a contender.

Ballmer has also put feelers out to Web leaders all over Silicon Valley of late, including former Facebook exec Owen Van Natta, to come and refurbish its Internet arm. Sources said Ballmer is also interested in execs like former CNET head Shelby Bonnie, as well as others.

One of the leading outside candidates was former AOL (TWX) head Jon Miller, who, sources said, told Ballmer yesterday that he does not want to be considered.

In fact, Miller is now likely to join the board of Yahoo as part of a deal the Internet company struck with activist investor Carl Icahn to cease his proxy fight.

Yahoo was, not surprisingly, top of mind in Ballmer’s speech before financial analysts yesterday at Microsoft’s Redmond, Wash., HQ.

Not surprisingly, Ballmer went out of his way to pooh-pooh Yahoo–a behavior that looks like it will become Microsoft’s latest weapon of choice for denigrating Yahoo and tanking its stock, in the wake of Yahoo’s rejection of Microsoft’s initial bid to buy the company outright and then, just its search business.

Pointedly calling the important search arena a “two-horse race” between Microsoft and Google–despite the fact that Yahoo is the No. 2 player, with a market share more than double Microsoft’s–Ballmer sounded more like a spurned swain for Yahoo’s affections.

Trotting out his somewhat inexplicable distinction of the Yahoo bid being “a tactic, not a strategy”–whatever!–Ballmer said: “We had a set of principles, we talked about them, it didn’t work out. … Fine, we’re done. We can move on.”

It seems Neil Sedaka was right: Breaking up is hard to do. As a parting shot, even though he was careful to leave the door open to future talks with Yahoo, Ballmer added: “People say ‘you have to buy Yahoo.’ … No, we don’t.”

Except Microsoft, um, does.

In any case, what the company will definitely do is spend more piles of money on its online business–an unspecified $500 million going forward, to be exact, which Ballmer said was critical to Microsoft’s future.

“There is this huge, huge, huge new opportunity around the Internet and online and we have to embrace that opportunity and invest in that opportunity,” Ballmer said.

That’s why some think Ozzie would be perfect for the job, now that the once fast-rising Johnson is gone.

He left, sources said, due to the collapse of the Yahoo deal, an effort for which Johnson served as point man.

Sources said that if the deal went through, Johnson would have run the Yahoo business, noting he has long indicated he wanted higher-level experience.

He will be getting that in his new job as CEO of Juniper Networks (JNPR), a quick move that many sources said surprised Ballmer and irked him (and things were already tense due to the failure of the Yahoo deal).

“Ballmer has to have a win here,” said one Microsoft source. “Even he can’t afford to miss again in this important space.”

That is the other certainty related to Microsoft’s rocky road on the Web: No, he cannot.

Please see this disclosure related to me and Google.

And in this departure of Kevin Johnson, president of Platforms and Services Division, from Microsoft–a big-deal job, let it be said–to become CEO of the network infrastructure company, Juniper Networks, is what my grandmother liked to call a beaut.

Johnson, I might remind you, was the point person on the software giant’s failed takeover bid to acquire Yahoo (YHOO), which rejected him and the rest of the Microsoft (MSFT) team over and over again in a very public fashion.

But who will Johnson’s most immediate Internet neighbor be when he takes up residence, presumably, at Juniper’s Sunnyvale, California, headquarters at 1194 North Mathilda Ave.?

Why that would be Jerry Yang at Yahoo HQ, 701 First Avenue, a mere half-mile away (see the Google map–oops!–below; click on it to make it larger)!

In fact, despite all the wrangling, Johnson and Yang still actually have a great deal of regard for each other, so one hopes the pair can all look forward to long CEO walks and lovely lattes together in the future.

(Kevin, Jerry will be right over with the welcome wagon full of purple and yellow Yahoo swag.)

Kevin Johnson (pictured here), the point person for Microsoft’s failed bid to buy Yahoo, is leaving the company to run Juniper Networks.

As the president of its Platforms and Services Division, the smooth Johnson has been trying, without much success, to beef up the software giant’s efforts in the Web space, especially in the online advertising arena.

He and Microsoft have had a little problem with that, largely due to an immovable object called Google.

In an attempt to make an end run around the search behemoth, Johnson led Microsoft’s attempt to take over Yahoo, the #2 player in the search and search advertising space.

The six-month effort, according to many sources at Microsoft, has led to a great deal of unrest at the company, including ire aimed directly at Johnson because of his perceived influence on CEO Steve Ballmer.

That got worse as Microsoft’s various tactics to grab Yahoo and later just its search business have failed again and again.

In truth, Johnson’s strategy of using Yahoo as an “accelerant” has been a sound one, playing to Microsoft’s strengths.

It includes a focus on servers (muscle), software (technology) and scale (bigger is better) that is tailor-made for giant like Microsoft, which must both jumpstart is long-suffering online services business and also keep its powerful Windows brand from weakening.

Microsoft’s recent Vista version of Windows has not been well-received, despite Microsoft’s claims that it is a success.

The company is now currently working on its roll-out of the next operating system, Windows 7. It will include touch technology and also be more integrated to its Live offerings.

In a memo to Microsoft troops today, Ballmer wrote: “The success of Windows is our number one job.”

At the same time, Microsoft has been trying to improve its online business, especially in search and display advertising. But its market share in the search market, for example, has persistently stayed under 10 percent.

Over the last year, Microsoft has tried to move forward via acquisition, such as its $6 billion purchase of online ad marketing firm aQuantive last August. It has also introduced new search innovations like a cash-back program.

But, most of all, it has zeroed in on Yahoo, which has a share in the mid-20s, in order to give it a better chance to compete with Google, the dominant market leader.

After first trying to buy Yahoo in a bit of a ham-handed manner, it turned to a plan to buy its search business.

That proposal has been rejected by Yahoo twice as not good enough for a variety of reasons, some better than others.

The hubbub sent Yahoo into the arms of Google, with which it struck an outsourcing ad search deal, which has attracted a lot of controversy, but will likely go forward.

Welcome to Microsoft’s nightmare!

With archrival Google allied with Yahoo, Microsoft has succeeded in burnishing its image as a Web also-ran and still has an uncertain path to change that.

What Microsoft will do next is unclear, as it now probably has to focus on getting its own house in order, before facing outward again.

To begin, the company said, Johnson’s large unit–which includes the powerful Windows division, as well as the online services business–will be reorganized into two parts.

The Windows and Windows Live online service will be one part and other will be made up of online advertising, search and MSN.

Perhaps in a sign to its troops and Wall Street–Microsoft’s stock has been swooning of late, due to its recent disappointing results–CEO Steve Baller will take over the Windows unit.

Reporting to him will be SVPs Steve Sinofsky (engineering), Jon DeVaan (development) and Bill Veghte (business).

Microsoft will search for a new head of its online business, who will also report directly to Ballmer. Until then, SVP Satya Nadella will run search, MSN and ad platform engineering efforts and SVP Brian McAndrews will continue to lead the Advertiser and Publisher Solutions Group.

Hey, Jerry Yang is looking pretty stable in comparison right now, doesn’t he?

Please see this disclosure related to me and Google.