Microsoft’s head of research and strategy showed off an interface concept back in February:
The most compelling ideas seem to be proactive software that anticipates next steps (but would you trust it to find the cheapest flight or know all of your obligations?) and a spacial environment that uses modal states to focus on specific task(s). However, all the spinning bits (“social radar” and alert) seem entirely gratuitous.
My favorite Microsoft interfaces remain the latest Xbox 360 update: *no longer available
And the next generation Xbox UI (due at year end):
Windows Media Center:
Kin Studio (apparently returning to Windows Phone soon): *no longer available