Anyone care to speculate with us as to why? 

Just weeks ago Carl Icahn went after eBay with a vengeance seldom seen even among acerbic activist investors, and demanded the company spinoff PayPal. He charged CEO John Donahoe with "inexcusable incompetence" and leveled serious accusations of conflict of interest against directors Marc Andreessen and Scott Cook. Icahn notified the company that he intended to nominate two directors, and to propose a non-binding resolution that would have shareholders vote on the spinoff at the annual meeting next month. 

Last week it all went away. eBay added corporate darling David Dorman to the BoD, evidently at Icahn's suggestion. Icahn withdrew his nominees and proposal. 

We speculate (in a current blog post) that Icahn couldn't win over other investors. He got what blessed little he could, and moved on. It's a good lesson for all activist investors: talk to other shareholders first.