Yesterday the Windows development team posted a lengthy blog post on the history of the Windows UI, and the thinking behind the decisions they are making for Windows 8.  Here’s an excerpt from that article:

“At the D: All Things Digital conference in June 2011, we demonstrated for the first time the new user interface that we developed for Windows 8. This new UI is fast and fluid to use, and optimized for mobile form factors such as laptops, tablets, and convertibles, where people spend the vast majority of their time today. Windows 8 works equally well with mouse, keyboard, or your fingers, and has the best pen support of any OS. It supports multiple displays and the widest array of configurations and form factors of any OS. On top of all that, Windows 8 introduces a new kind of app, which we codenamed “Metro style” following the design language that has evolved going back to Windows Media Center and the new Windows Phone. These apps are immersive, full-screen, beautiful, and optimized for the ways that people commonly use devices today.

I thought it would be useful to take a step back and describe a little bit of the background of how the Windows 8 user interface was designed, and discuss some of the decisions we’ve made and the goals of this new experience in more detail.” - by Jensen Harris, Director of Program Management for the User Experience.

See the full article @ http://blogs.msdn.com/b/b8/archive/2012/05/18/creating-the-windows-8-user-experience.aspx.