Enter Arianna, Exit AOL Media President

In the newly merged AOL newsroom, everyone surely saw it coming. With Arianna Huffington now editor in chief for all AOL content as part of the tech company's merger with the Huffington Post, the current content chief is leaving.

AOL Media president David Eun, who joined the company last year from Google to oversee news and video, said that his supervisors wanted him to stay on, but he saw no way to stick around.

"There isn’t a role that matches what I am seeking to do," Eun says in a memo to staff, in which he listed the accomplishments of the team, with himself at the helm, as well as the friendship he had with Huffington.

Huffington, cofounder of a liberal-leaning blog that turned into a publishing powerhouse within six years, is the name that drew AOL to plunk down $315 million. So it stands to reason that her new role would shake up the AOL operation going forward.

Other changes include Jon Brod, who was in charge of AOL Ventures, being named as the new COO of the Huffington Post Media group within AOL, which includes all of its editorial content.

The AOL shakeup is not the only change at the top for big-name media properties lately, and it’s a sign of how big changes or style clashes can prompt top media executives to either walk away or be walked out, sometimes in surprisingly short order.

Time Inc. CEO Jack Griffin was sent packing after just six months on the job with Time Warner CEO Jeff Bewkes saying he “did not mesh with Time Inc. and Time Warner.”

After this unusually public throat-slitting, anonymous colleagues quickly filled in the blanks, saying that Griffin was militaristic and that he brought in outside consultants to make changes at the company, which some took as an insult, and that his presence led to the departure or forced exit of several top executives.

One defender told the Times that “entrenched interests” who resisted change were behind his departure. Rather than skulking off quietly, as is typical in the glossy world, Griffin issued a statement touting his history of getting results, a history that continued as he led the business transformation at Time Inc. "My exit was clearly not about management style or results," he said.

Another media exec who seemingly had a pair of running shoes under the desk? Stephen Drucker, who took the helm of Town & Country in April 2010 after departing House Beautiful. He left in January 2011, with a little less than a year on the job, apparently of his own volition.

There was some suggestion that his departure had to do with his putting the Barefoot Contessa, Ina Garten, in the magazine, and that it was a conflict of interest because Drucker’s partner worked with the Contessa on merchandising projects, but Hearst shot that theory down, and media watchers concluded that it had to do with subscription and ad woes.

If there is a lesson in the quick pace of departures for media executives, it's this: Whether your bosses give you a shove on the way out (as was the case for Griffin) or you face being publicly demoted if you stay, as was the case for Eun, get the last word. Have a statement of your accomplishments to email to your staff and a Twitter page ready to go.

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