After 18 months as CNN chairman, Walter Isaacson, 50, announced Monday that he was resigning, effective this spring, to run the Aspen Institute think tank. ''I have long yearned to have another phase in my life after journalism and leading the Aspen Institute is a perfect fit,'' he told CNN staffers in a memo. Isaacson, who came to CNN in 2001 after acting as editorial director of Time Inc. (the magazine publishing arm that includes Entertainment Weekly and EW.com), was credited with bringing stars like Connie Chung and Paula Zahn to the news network. However, his tenure also marked the period when CNN went from being the cable news ratings leader to being a struggling second against rival Fox News Channel.
Isaacson's announcement came days after an exodus from CNN of six anchors and correspondents. (ABC and NBC veteran Garrick Utley told the New York Daily News he chose to leave; the others were told their contracts would not be renewed.) It also comes a day after AOL Time Warner chairman Steve Case announced he would step down, citing shareholder concern with the decline in the company's stock price since he orchestrated the merger of AOL and Time Warner three years ago.