It looks like Terry Myerson, who has headed up engineering efforts for the group, will take over many of Lees' responsibilities, though, he won't be inheriting his title. At least not just yet. In a memo seen by AllThingsD, Ballmer announced that Lees would be taking on a new position with the company, though it's not entirely clear what that might be -- describing it only as "time-critical" and "focused on driving maximum impact in 2012 with Windows Phone and Windows 8." (So, it's safe to assume he's not becoming a janitor.) The shakeup isn't terribly surprising, especially considering the CEO's own admission that Windows Phone 7 was not performing as well as expected in the market.