Sources said a more substantial public announcement has been pushed by Yahoo’s board–apparently, an internal email to employees was considered too–to show Yahoo’s new team and that the company still has a strong bench, despite a lot of exec departures of late.

As we already wrote, the structure will pivot on several key execs, reporting to President Sue Decker.

EVP of Yahoo’s Platforms and Infrastructure division Ash Patel as head of a new Audience Products group (its name was changed from Global Products); Global Partner Solutions EVP Hilary Schneider as the head of a new U.S unit; various folks running around the rest of the globe.

There will also be another strategy team group with a new head, who has not yet been chosen.

And Yahoo will name Scott Dietzen (pictured, right) to take over part of the job of SVP Brad Garlinghouse, who running was running all communications properties and products. Dietzen will get the communications portfolio, which includes email and messaging, all under Patel.

(Community properties like Flickr will actually move under Front Door Head Tapan Bhat, who also reports to Patel.)

Dietzen was the president and CTO of Zimbra (and before that CTO of BEA Systems), the highly innovative open-source email startup Yahoo bought last fall for $350 million.

Garlinghouse (pictured, left), as we reported last night, will not be officially leaving until the end of the summer, though. He is currently traveling in Asia, sources said, and has not yet decided on a new gig.

He is, of course, the man who wrote the infamous “Peanut Butter Manifesto,” which first revealed deep tension within Yahoo.

Yahoo is likely to also announce changes in the engineering organization under CTO Ari Balogh, who is also orchestrating some massive and much-needed changes in the arena at Yahoo.

If Yahoo CEO Jerry Yang thought Microsoft CEO Steve Ballmer was scary, meet persnickety investor Carl Icahn.

According to CNBC, which was doubtlessly leaked the threat by the clever billionaire to test the waters, he has bought as much as 50 million shares in the troubled Internet company as part of a potential proxy fight.

Following the CNBC report, The Wall Street Journal reported that Icahn was leaning toward launching the proxy fight, using that 4% stake he has apparently amassed since the Yahoo-Microsoft tussle ended May 3.

Another activist investor, The Journal said, also thinking of getting involved was Firebrand Partners’ Scott Galloway, also known as the thorn in the New York Times’s side. (His SuperPoking inexplicably did nab him a board seat.)

Oh, dear.

But sharks do come when there is blood in the water, of course, as there has been since Microsoft (MSFT) abandoned its takeover quest for Yahoo (YHOO) after repeated rejection from Yang and its board.

It is not clear what Microsoft will do.

Icahn’s efforts seems clever, using similar tactics as he did in the BEA Systems-Oracle fight, trying to get just a few board seats to force Yahoo to sell to Microsoft.

But he better hurry–anyone wishing to wage such a proxy battle has until Thursday to do so to get on the slate at Yahoo’s July board meeting.

In honor of the Icahn entry, here’s an anticipatory video for Yang for the meeting, so he knows just what’s coming: