[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.

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.

BoomTown was all busy trying to think of execs to replace Yahoo CEO Jerry Yang, as pressure mounts on him to right the troubled Internet company.

But now, Yang’s position feels safer than ever and it’s his nemesis–Microsoft– that needs a new leader for its long-stumbling online services business.

Microsoft (MSFT) was already cracking, according to sources, and had a wish list of internal and external candidates that CEO Steve Ballmer is now considering.

Ballmer noted in his memo to company employees yesterday the departure of Platforms and Services President Kevin Johnson and the reorganization of that massive division, that he would “create a new senior lead position and will conduct a search that will span internal and external candidates.”

Many think, given the turbulence, that Ballmer will pick a trusted internal Microsoft veteran, especially since he probably should move quickly.

Sources said Brian McAndrews (pictured here), who came to Microsoft via the $6 billion aQuantive acquisition last year, is the leading insider for the job.

SVP Satya Nadella, who will run search, MSN and ad platform engineering efforts in a new reorg, is less likely.

But Strategic Partnerships Senior Vice President Yusuf Mehdi, a longtime exec who has previously led online businesses at Microsoft, is also in the mix, the possible dark horse due to his past experience. As strategy “wingman” to Johnson, he might want a more operational job again now that Johnson is gone. Mehdi is also well liked in Silicon Valley and in media circles.

More interesting perhaps is one of the top outside candidates on the list, former AOL head Jon Miller (pictured here), who is poised to be added to the–wait for it–Yahoo (YHOO) board, as part of its recent proxy fight settlement activist investor Carl Icahn.

Miller, who was bounced out of AOL unfairly several years ago, is now running an investment firm with former Fox Interactive Media head Ross Levinsohn.

(And, adding to the hijinks, Levinsohn was on Microsoft’s alternate board in its own abandoned proxy fight against Yahoo.)

Other execs on the list are also more experienced in the Web space, such as former CNET head Shelby Bonnie, who is currently working on a start up called PolticialBase.

Microsoft sources said someone like former Yahoo COO Dan Rosensweig–now in private equity at the Quadrangle Group–is also the type of exec the company is looking for. Of course, he is deeply loyal to Yahoo (and his name has also been bandied about as a possible future Yahoo CEO too).

Of course, the company’s fondest desire is probably to get an even bigger Web or media exec like News Corp.’s (NWS) Peter Chernin or former eBay (EBAY) head Meg Whitman. (News Corp. is the owner of Dow Jones and of this Web site.)

Having been around when Microsoft first dipped its toe in Internet waters back in the mid-1990s, I’m sorry to say that whoever the software giant picks has small shoes to fill.

After years and years of losses, while Google (GOOG) and Yahoo made bank and grabbed share, Microsoft has not.

In its recent quarterly report, for example, while revenues for the online business rose 24 percent to $838 million, losses from Platforms and Services doubled to $488 million.

Ouch! That’s gotta hurt.

Because of the continued inertia, 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.

That division needs to bulk up the software giant’s efforts in the Web space, especially in the online advertising arena where Google now rules.

In an attempt to make an end run around the search behemoth, Microsoft tried to buy Yahoo, the No. 2 player in the search and search-advertising space, and then tried to grab only its search business–efforts that have so far yielded nothing.

In any case, this reorg of a previous reorg (Ballmer united the Windows and online services business three years ago) is a clear signal of the unrest and even a bit of chaos at Microsoft resulting from the Yahoo battle.

There is definitely a lot of ire aimed directly at Johnson (pictured here) as the key executive in charge of the effort besides Ballmer, because of his failure to make a deal.

Worse, the bid forced Yahoo into the arms of Microsoft archrival Google, via a controversial search-ad outsourcing deal.

Microsoft must obviously do something.

Its market share in the search market, for example, has persistently stayed under 10 percent, despite a range of efforts to differentiate itself.

Re-energizing Microsoft’s Web efforts is most definitely a thankless job.

And whether replacing Johnson and bringing in a new leader who can push the reset button will work this time is unclear, as are many things having to do with Microsoft’s Internet strategy right now.

Please see this disclosure related to me and Google.