Barry Diller—a man who seemed positioned to reign opulently over his IAC media empire for years to come—announced this morning that he's stepping down as CEO of IAC.

In a press release this morning, IAC announced that Diller is stepping down as IAC's CEO. He'll be replaced by Greg Blatt, the former CEO of Match.com. Diller's not leaving the company entirely; he'll stay on as chairman of the board and "senior executive." He still owns more than a third of IAC's stock, the largest voting stake of any shareholder.

The other half of the announcement is big, too: IAC is ending its long but often contentious relationship with John Malone's Liberty Media. IAC is buying back its stake from Liberty for $220 million; Liberty will get Evite and Gifts.com from IAC as parting gifts.

Here's Diller's explanation, from the release:

"It's been clear to me for some time that this Company needs a full time aggressive and aspirational executive in the CEO role. While I'm not going anywhere, IAC, with its operating businesses growing, large cash resources and virtually no debt, needs the kind of leadership that Greg Blatt can bring it in order to continue to grow and thrive many years into the future," said Mr. Diller...

"As noted above, I have the right, and the intention to purchase additional shares over the next 9 months that will increase my voting share to over 40%. I want this to be a long term holding for me and my family and I want this well capitalized and growing Company to be of enduring ambition and naming a new CEO is critical to that goal."

It's clear that resentment over Diller's management style has been brewing at IAC for some time. And his private life has come under an uncomfortable spotlight around here for some time, as well. Still, this is rather sudden. If you're an insider who knows more, email us.

[Photo: Getty]