It seems that since Yahoo CEO Carol Bartz is playing it coy about whether she wants to do a massive search deal with Microsoft or not, the software giant is just going to keep hiring her search tech team out from under her.

Today, Microsoft (MSFT) said it had hired Larry Heck, VP of search & advertising sciences at Yahoo Labs, who will work in its online unit.

It’s like the rapture, except geekier.

Said a Microsoft spokeswoman: “We are happy to confirm that Larry Heck has accepted a job at Microsoft. He will be working for Satya Nadella, SVP, research and development, online services division, and he will start in a few weeks time. We look forward to welcoming him to the team.”

[UPDATE: Yahoo sources said Heck was laid off in December, so it is not quite the daring raid that it seems.]

Nonetheless, it is the third big hire from Yahoo’s search tech team by Microsoft. The first was Sean Suchter, followed by Qi Lu, who now heads Microsoft online services team.

Lu is a big draw for search engineers and was close to Heck, and sources said there are several other Yahoo tech execs likely to move too.

The boatloads of money Microsoft has been spending in the arena to catch leader Google is certainly a draw. Microsoft is No. 3 behind both Google (GOOG) and Yahoo (YHOO).

In addition, MSN recently nabbed Yahoo media head Scott Moore to run its U.S. programming, along with Yahoo marketing exec Eric Hadley.

Jill Nash, Yahoo’s chief communications officer, has told CEO Carol Bartz and other Yahoo staff this afternoon that she is leaving the company.

Yahoo has not made Nash’s resignation official, but is likely to do so quickly as Bartz tries to stanch incessant leaks (like this one; see below!).

In any case, sources said Nash does not appear to have any definite plans to move to another company immediately, so the reasons for her departure are unclear.

BoomTown would have to guess that Nash is simply completely spent from her past two years at Yahoo (YHOO), which have been very fraught from a public relations perspective, to say the least.

Nash, who was hired by former CEO Terry Semel, has had to deal with everything from management turmoil, after Semel was replaced by co-founder Jerry Yang, to poor financial results to a nasty takeover attempt by Microsoft (MSFT) to an even less friendly proxy fight to a failed search deal with Google (GOOG) to recent wrenching layoffs.

Not much good news to report, in other words, especially with a tough turnaround road ahead with newly installed CEO Bartz, who seems to have a very strong mind of her own about public relations.

(Including, several sources tell me, this week in an internal memo, offering cash rewards to employees who turn in other employees who leak to the press. Bartz has also initiated investigations to stop leaks. All I can say about these tactics–while it might seem reasonable to try to stop the leaking, from a management perspective, and I see why Bartz is focusing on it–is: Yahoo is not a prison and its employees are not snitches and–more to the point–they won’t leak to me if Bartz fixes the company.)

While I have not always seen eye-to-eye with Nash on this column’s coverage of Yahoo, I have found her to be a pro to deal with and fair, especially considering the often tense circumstances at Yahoo in the last year.

Nash is not the first top Yahoo exec to depart since Bartz got to Yahoo in mid-January and will not likely be the last, as the new CEO carves out her own path and chooses the team she wants.

Many Yahoos have told me, not for attribution and at all levels of the company, that they are bone-tired of the long-term struggle the company has been engaged in and want to move on, even in this weak economic climate.

Last week, this column reported the departures of Zimbra co-founder Satish Dharmaraj and marketing exec Eric Hadley, neither of which was necessarily due to Bartz’s arrival.

Now it’s Nash’s turn to say goodbye. According to Yahoo’s Web site, her duties were to lead its outward-facing efforts.

It reads, in part: “As a key member of the Yahoo! executive team, Nash will be responsible for the company’s worldwide communications efforts, including public and media relations, corporate reputation, corporate, financial and employee communications, and crisis and issues management.”

Nash came to Yahoo from the Gap, where she was the VP of global corporate communications. Previous to that, she worked at Charles Schwab (SCHW), KPMG and Transamerica Life.

With Yahoo earnings expected to be dismal when the company reports fourth-quarter earnings this Tuesday afternoon, new Yahoo CEO Carol Bartz is going to have to hang tough.

And she certainly seems capable of that. At her first all-hands meeting, Bartz (pictured here) said, according to one report others have since confirmed to BoomTown, that she would “drop-kick to f***ing Mars” employees who leak to the press.

That threat sent little shivers up BoomTown’s spine too, which is why it must have taken so long for her first-week missive to Yahoo (YHOO) staff worldwide to get to my inbox.

Well played, Ms. Bartz, well played. (Plus, I really am bad at football metaphors.)

But turnabout is also fair play. And that’s why I am redoubling my efforts to bring you up-to-date news from Yahoo under Bartz’s leadership, as ATD has done so obsessively during the reigns of ex-Yahoo CEOs Terry Semel and Jerry Yang (and, if you want to really date me, Tim Koogle).

In that spirit, this column broke the news last week that Zimbra founder Satish Dharmaraj and marketing exec Eric Hadley were leaving.

And the week before that Yahoo Chairman Roy Bostock was swanning around Manhattan with Microsoft (MSFT) CEO Steve Ballmer and Time Warner (TWX) CEO Jeff Bewkes.

More to come this week, for sure, as all eyes turns to Yahoo’s financial performance (which is no fault of Bartz’s, who’s just arrived but still has to deliver the news).

But until then, here’s that energetic memo Bartz sent out to Yahoo troops after her first week there.

From: Carol Bartz
Sent: Friday, January 16, 2009 3:12 PM
To: all-worldwide@yahoo-inc.com
Subject: My First Friday

Carol

One of Yahoo’s top marketing execs, Eric Hadley, who came to the company with a lot of acclaim in only November, is set to leave for a new job working in branding and global marketing for Microsoft’s MSN online service, several sources said.

Hadley had previously worked at Microsoft (MSFT) as GM of global advertising solutions and marketing support at MSN, although he had come to Yahoo (YHOO) from a job at Heavy.com as its chief marketing officer.

At Yahoo, he was hired as its VP of U.S. field marketing. In a statement at the time of his hire, Yahoo’s marketing and customer care SVP, Nick Besbeas, said it was a “a newly created role responsible for marketing communications strategy and execution for advertisers, publishers, industry groups and other partners.”

It’s yet another sign of renewed executive unrest at Yahoo, which continues in the wake of the hiring of new CEO Carol Bartz. Yesterday, BoomTown reported that Zimbra founder Satish Dharmaraj was leaving Yahoo, which was confirmed by the company later in the day.

Hadley seemed excited by the new role at Yahoo only a few short months ago. In his statement then, he said: “I’ve always admired the Yahoo! brand, the spirit of innovation and results Yahoo! provides for advertisers. I am very excited to be joining this great team and look forward to helping take the company to the next level.”

Well, maybe not the next level, which Yahoo is trying to reach under Bartz.

The departure of both execs is not likely related directly to her arrival, as sources at Yahoo said that the hard-charging new CEO had not yet met with all its top execs to assess the bench strength at Yahoo, or brought in any new execs save her own longtime administrative assistant.

So far, many of the troops at Yahoo seem jazzed by Bartz’s arrival as it signals change and she is known for making decisions quickly.

But the uncertainty of a new CEO and continued talks with Microsoft and Time Warner (TWX) unit AOL about various partnerships have continued to jar many at Yahoo too.