This week Microsoft unveiled a completely redesigned version of their flagship OS. Codenamed Windows 8 (not much of a codename is it?), this version is intended to work on both traditional mouse and keyboard configurations as well as tablets. Whether a touch-friendly shell on top of the old Windows codebase is the right approach or not, there’s no denying that the UI team at Microsoft has been busy creating some pretty nice touch UI. There’s also no denying the influence of touch UI on desktop OSes. Apple’s next release of OS X, dubbed Lion, is also bringing many touch and mobile UI conventions to their desktop OS.

Chromeless UI

The first thing you’ll notice about Windows 8 is the “chromeless UI” which borrows heavily from the  Windows Phone 7 Design Guidelines. In particular, the concept that content is the interface. The result is a very clean interface that allows the user to directly manipulate content instead of buttons or links. Also borrowed from WP7 are the live tiles present on the start screen.

Bezel Gestures (“Egde UI”)

Windows 8 also makes extensive and very sensible use of the screen bezel. Microsoft calls this their “Edge UI” and it allows users to perform a number of critical tasks without cluttering the UI. Bezel gestures also reduce the level of effort needed to perform common tasks, since the user’s hands are naturally near the edges when holding a device. The left and right bezels are reserved for app switching and OS-level menus while the top and botttom bezels are reserved for contextual app menus. It’s a very elegant design. RIM’s Playbook also makes use of the tablet bezel in it’s design and it will be interesting to see if Apple introduces similar interactions in the next release of iOS.

Window Snap

Borrowing from Windows 7, Windows 8 has a “window snap” feature that allows users to view two apps at the same time, one in a sort of skinny mode and the other in a sort of fat mode. A handy slider allows you to determine which is which. Use of the quick app switching gesture will let you swap out either of the two panels with a different app.

Thumbs Keypad

The Windows 8 tablet mode has been optimized for a 16:9 ratio that is movie friendly. This makes for a pretty wide screen in landscape mode and as a result can make typing while holding the device in landscape darn near impossible (the same is true for the 4:3 iPad). To accommodate for this problem, Microsoft is introducing a thumbs-friendly keyboard that essentially splits the keyboard in two and places the keys within easy reach of the thumbs. Clever.