Yahoo’s SVP of North American Audience, Jeff Dossett, is leaving the company.

Reasons for the departure are personal, said sources, who said that Dossett (pictured here) is most likely to do a start-up.

Dossett did not return emails asking for comment, but Yahoo (YHOO) confirmed the departure to BoomTown.

It was announced internally that Dossett has resigned and his responsibilities have been assumed by Jimmy Pitaro, who runs Vertical Audience Experiences for Yahoo, and Tim Mayer, who is in charge of Search & Social Applications. They will jointly lead the North America Audience business, reporting to U.S. EVP Hilary Schneider.

Dossett has been in charge of all of Yahoo’s media assets, including its powerful News, Sports and Finance content sites.

He has been rejiggering the media unit since he arrived last year, including centralizing product development.

Dossett joined Yahoo last November, coming to the company from Microsoft (MSFT), where he was MSN executive producer and general manager.

In his job at MSN, Dossett was the lead for audience, content and programming strategy and execution in the U.S.

He had worked at the company since 1991, in a variety of sales and marketing jobs in Canada, and later worked on strategy and business development for MSN.

Dossett was also CEO of Carpoint, now MSN Autos, and was GM of its real estate arm.

He also took two years off from Microsoft in 2002 to climb the highest mountains on each of the seven continents, finally reaching the summit of Mount Everest in May of 2004.

Dossett reached the summit of Everest again for a second time last year.

Here’s my favorite quote from former Microsoft exec Jeff Dossett from a phone interview he gave to BoomTown this afternoon, after his appointment as Yahoo’s new U.S. Audience head:

“Where others see risk, I see opportunity,” said the man who has climbed Mount Everest twice. “We have this great Web asset … and, from here on out, it is all about execution.”

(Speaking of which, the photo above of Dossett is on the summit of Everest, taken by one of his TEAM INSPIRED climbing partners, David Morton, on May 22, 2008.)

You can tell from the gumption in this ain’t-no-mountain-high-enough sentiment that Dossett just got to Yahoo (YHOO) and sees a challenge at the troubled Internet giant where others see, well, a long-running quagmire.

I like him already!

“If you take a look at it, Yahoo has so many incredible assets,” said Dossett, who is replacing Yahoo Media Group SVP Scott Moore, whose departure from Yahoo was reported here first today. “There is an unparalleled level of audience to build on.”

You won’t get an argument from me on that obvious fact, because amazing content and communications assets have always been Yahoo’s crown jewels.

It’s the management–or lack thereof–of its products and staff by Yahoo’s leadership and board that’s been the problem.

So it is probably a good idea that Yahoo has brought in new blood to shake things up more. Yahoo CEO Jerry Yang has been looking outside the company of late to recruit outside talent.

Dossett was one of these execs, as I had written a month ago in a post titled “The Secret Microsoft Invasion of Yahoo Continues: MSN GM Headed There Soon?”

With its stock in the perpetual doldrums, the graphical advertising business outlook glum and a lucrative search ad deal with Google (GOOG) trapped in a Justice Department lockbox, the company could use someone to rattle its cages.

In the interview, Dossett (pictured here) acknowledged that he had been speaking to Yahoo U.S. head Hilary Schneider about a range of jobs related to business development. But when Moore told Schneider he was leaving, “We both thought I might be able to play a larger role.”

Dossett said that he hoped to be able to continue to keep Yahoo the No.1 or No. 2 content destination over a range of categories and also push forward more integration with Yahoo technology offerings such as email, calendar and others popular consumer tools the company has.

“There is a tremendous need to integrate … to create the largest and most engaged online audience,” he said. “It all still needs to be stitched together.”

Well, it has not exactly been a very successful quilting bee as yet. Yahoo has continued to struggle to make a more seamless offering to meet the changing needs of consumers, many of whom have been moving more toward more integrated social-networking experiences like those offered by Facebook.

“There is so much more we can do,” said Dossett. “We have only really scratched the surface to combine what we have.”

Dossett, who said his departure from Microsoft (MSFT) was cordial, would not comment on what a combination of Yahoo with the assets of Time Warner (TWX) online unit AOL would look like though.

Yahoo and AOL have been engaged in long-running talks about a merger, a new company in which Dossett would now play a large role, if a deal was ever to be struck.

It will be a big challenge that will surely test Dossett, a longtime and experienced mountain climber, who has spent much of his career at Microsoft.

That includes during the period over the last year in which the software giant was trying to take over Yahoo without being too polite about it.

In his job at MSN, Dossett was the lead for audience, content and programming strategy and execution in the U.S.

He had worked at Microsoft since 1991, in a variety of sales and marketing jobs in Canada, and later worked on strategy and business development for MSN.

Dossett was also CEO of Carpoint, now MSN Autos, and was GM of its real estate arm.

At Yahoo, he joins another former Microsoft big shot and close colleague, Joanne Bradford, who started her job as Yahoo’s top U.S. ad sales exec last month.

Dossett also took two years off from Microsoft in 2002 to climb the highest mountains on each of the seven continents, finally reaching the summit of Everest in May of 2004.

Dossett reached the summit again for a second time this past May.

Somehow, I think he will find the air at Yahoo just as thin.

About a month ago, BoomTown reported that MSN executive producer and general manager Jeff Dossett (pictured here) was contemplating joining Yahoo.

Microsoft (MSFT) released a statement that day saying Dossett was indeed stepping down from his MSN duties, as I had posted, but noted that he was staying put at the software giant.

Oops, it looks like I was right in my initial report: “The Secret Microsoft Invasion of Yahoo Continues: MSN GM Headed There Soon?”

Dossett has accepted a job as SVP, U.S. Audience at Yahoo, Yahoo (YHOO) said in a press release this afternoon.

“I am very excited about this new leadership opportunity at Yahoo,” wrote Dossett in an email to me. “Of course, I have great respect for my many friends and colleagues at Microsoft and I wish them well.”

But is the hire linked to my report earlier today of Yahoo Media Group SVP Scott Moore leaving?

You betcha, as Governor Sarah Palin says.

While the company had already been deep in conversations with Dossett for another job, as head of business development, management scrambled after Moore reportedly told Yahoo of his plans to leave a week ago.

After BoomTown this morning reported that Moore, as well as Yahoo News general manager Alan Warms, were departing later this week, Yahoo confirmed the departures this afternoon.

Dossett will report to Hilary Schneider, executive vice president of Yahoo U.S., and fill the role previously held by Moore, although the title is different. Yahoo said Moore was leaving “to pursue other opportunities.”

A Yahoo spokesman also said later about Warms:

“We’ve worked with Alan over the last couple of months on an orderly transition plan of his responsibilities over to Neeraj Khemlani, who will continue to lead Programming & Development for News & Information at Yahoo. We wish Alan much success in his future endeavors and know that Neeraj will continue driving Yahoo News to even greater success.”

Dossett will have presumably have purview over all that and more.

A longtime and experienced mountain climber, he has been one of the more senior digital execs at Microsoft.

The reason given for Dossett’s departure from Microsoft, announced internally in mid-September, was to also “pursue other opportunities” (I still love this phrase, as oily as it is.)

As I wrote then: “While the hire is not yet complete, that apparently means that he is likely going to rival and onetime Microsoft quarry Yahoo as a senior exec.”

It has all been an interesting digital-musical-chair trend, in fact. Also last month, another former Microsoft big shot, Joanne Bradford, started her job as Yahoo’s top U.S. ad sales exec.

Bradford came to Yahoo after a very short stint as national ad sales head at the trendy Los Angeles start-up, Spot Runner.

Previous to that, Bradford (pictured here) had been at Microsoft for many years, most recently as VP and chief media officer of MSN Media Network.

While at Microsoft, Jeff Dossett was a close colleague of Bradford, so his moving to Yahoo is probably not that much of a surprise.

Outgoing Yahoo Media Group SVP Moore, who has been at Yahoo since 2005, is another former Microsoft digital exec, where he worked all over the company.

In his job at MSN, Dossett was the lead for audience, content and programming strategy and execution in the U.S.

He had worked at the company since 1991, in a variety of sales and marketing jobs in Canada, and later worked on strategy and business development for MSN.

Dossett was also CEO of Carpoint, now MSN Autos, and was GM of its real estate arm.

He also took two years off from Microsoft in 2002 to climb the highest mountains on each of the seven continents, finally reaching the summit of Mount Everest in May of 2004.

Dossett reached the summit of Everest again for a second time this past May.

Here is Yahoo’s press release about his appointment in its entirety:

JEFF DOSSETT JOINS YAHOO! TO LEAD US AUDIENCE BUSINESSES

In 2002, Dossett took two years away from his career at Microsoft to pursue his passion for adventure with a goal to climb the highest mountain on each of the seven continents, known as the “Seven Summits.” Reaching the summit of Mount Everest on May 24, 2004, Dossett became the third Canadian in history to successfully complete the Seven Summits. On May 22nd, 2008, Jeff became the second Canadian in history to reach the summit Mount Everest for the second time. He serves on the Board of Advisors of VillageReach (www.villagereach.org), GOOD Worldwide Inc. (www.good.is), and Live Mocha (www.livemocha.com). Dossett holds a degree in business administration with honors from the Richard Ivey School of Business at the University of Western Ontario in Canada.

A longtime and experienced mountain climber, Dossett (pictured here) has been one of the more senior digital execs at Microsoft.

The reason given for Dossett’s departure from Microsoft (MSFT), announced internally this afternoon, was to “pursue other opportunities.”

While the hire is not yet complete, that apparently means that he is likely going to rival and onetime Microsoft quarry Yahoo as a senior exec.

It is an interesting digital-musical-chair trend, in fact. On Monday, another former Microsoft big shot, Joanne Bradford, will start her job as Yahoo’s top U.S. sales exec.

Bradford came to Yahoo (YHOO) after a very short stint as national sales head at the trendy Los Angeles start-up, Spot Runner.

Previous to that, Bradford (pictured here) had been at Microsoft for many years, most recently as VP and chief media officer of MSN Media Network.

While at Microsoft, Jeff Dossett was a close colleague of Bradford, so his moving to Yahoo would not be that much of a surprise.

But one has to wonder what other Microsoft execs Bradford can entice to come to Yahoo, especially given that CEO Jerry Yang is reportedly interested in aggressively beefing up his executive ranks after more than a year of employee attrition due to all the turmoil at the company.

Current Yahoo Media Group SVP Scott Moore, who has been at Yahoo for several years now, is another former Microsoft digital exec.

What Dossett would do if he takes a job at Yahoo is unclear.

But, in his job at MSN, Dossett was the lead for audience, content and programming strategy and execution in the U.S.

He has worked at the company since 1991, in a variety of sales and marketing jobs in Canada, and later worked on strategy and business development for MSN.

Dossett was also CEO of Carpoint, now MSN Autos, and was GM of its real estate arm.

He also took two years off from Microsoft in 2002 to climb the highest mountains on each of the seven continents, finally reaching the summit of Mount Everest in May of 2004.

Dossett reached the summit of Everest again for a second time this past May.