Microsoft's Steve Ballmer confirmed at the Microsoft's Developer Forum in Tokyo, Japan that Windows 8 is on schedule to be released in 2012, after leaked rumours from various hardware vendors including Intel provided inaccurate details. He did not provide much information, but here's one quote:

We're obviously hard at work on the next version of Windows... We have a brand new user interface. We've added touch, and ink, and speech. And yet, as we look forward to the next generation of Windows systems, which will come out next year, there's a whole lot more coming.

As we progress through the year, you ought to expect to hear a lot about Windows 8. Windows 8 slates, tablets, PCs, a variety of different form factors.