Microsoft tablet OS not coming until fall 2012?

We've caught wind of many whispers about a Windows designed specifically for tablets, but the latest scuttlebutt states we won't get to add them to our mobile arsenal anytime soon -- Bloomberg's anonymous sources report that Microsoft won't release a tablet operating system until the 2012 back-to-school season, and will only begin to publically test the OS at the end of this year. That suggests not only a timeframe, but also a likely plan -- it's not hard to imagine Microsoft would enjoy a slice of the educational market before iPads replace textbooks entirely at schools with cash to burn. Of course, Dell seems to think there'll be a Windows 8 slate in January of next year.