Ms. Clarizio, the former president of Advertising.com, was placed atop Time Warner's various online advertising acquisitions after Platform-A's first president, Curt Viebranz, was ousted last spring after five months in the job. Mr. Viebranz came from Tacoda, one of seven companies including Ad.com, Third Screen Media, AdTech and Quigo that were rolled up into Platform-A, the world's largest ad network by reach.
Ms. Clarizio had spent 10 years at AOL and then Advertising.com after the company was acquired in 2004. She also headed sales for AOL's own advertising inventory.
An executive close to the situation said AOL CEO Randy Falco made the move because he believes that now that integration of the disparate units is complete, Platform-A needs a stronger sales leader to make the structure deliver in a tough economic environment.
Mr. Coleman worked for seven years at Yahoo and led both display- and search-ad teams before joining ad-targeting start-up NetSeer as CEO last year. In a memo to staff, Mr. Falco acknowledged that Coleman's job won't be easy.
"No doubt Greg is joining Platform-A at a difficult time," he said. "The deepening economic recession is affecting every corner of the economy, including our own."
Mr. Falco thanked Ms. Clarizio for her contribution to Platform-A but described Mr. Coleman as the best person to lead it going forward.
"Now we have the opportunity to build on this foundation and expand premium branded display sales across our extensive and fast-growing MediaGlow programming network," he said. "And Greg, who has 25 years of media sales and publishing experience, is ideally suited to lead this effort."
Corporate parent Time Warner will report earnings tomorrow, and they're expected to be weak. Third-quarter sales at AOL were down 6%, and Bernstein Research analyst Michael Nathanson is predicting fourth-quarter advertising sales at AOL will be down 18.2%.
Last week, AOL announced it would lay off 700 people, or 10% of its work force, and freezing merit-based pay increases in 2009.