Microsoft Entertainment Division president Robbie Bach has retired.

MAY 25, 2010 • Robbie Bach resigned as president of Microsoft’s Entertainment and Devices Division. Bach has been with the company since 1988, and will remain through the fall. Games business chief Don Mattrick, and Andy Lees in charge of the division’s mobile-phone business, will report directly to chief executive Steve Ballmer.

Impact: Despite the occasional Games for Windows window dressing, Microsoft pretty much bet the farm on becoming a big shot in console gaming. After Natal launches, there’s not much change on the horizon as the company milks as many years as possible out of its Xbox 360 technology.  Given that scenario, perhaps Microsoft no longer needs a Robbie Bach to shepherd the division’s operations. His departure may also mean there is confusion at the top as to where to place bets on the next big trend in console gaming.  Everyone but Nintendo missed the Wii/casual phenomenon. Now social networks and mobile games are all the rage. Dynamics like that often lead to senior management changes at companies who didn’t see the train coming.