I just recently read about this rumored Windows OS, known as Windows 7 or codename “Vienna.” Now I knew about Windows 7 coming out thanks to Gizmodo having screenshots of Windows 7 Mobile. According to Windows Vista Update, Vienna aka Blackcomb is:
Originally, internal sources pitched Blackcomb as being not just a major revision of Windows, but a complete departure from the way users today typically think about interacting with a computer. While Windows Vista is intended to be a technologies-based release, with some added UI sparkle (in the form of the Windows Aero set of technologies and guidelines), Vienna is targeted directly at revolutionizing the way users of the product interact with their PCs.

For instance, the “Start” philosophy, introduced in Windows 95, may be completely replaced by the “new interface” which was said in 1999 to be scheduled for “Vienna” (before being moved to Vista (“Longhorn”) and then back again to “Vienna”).
Interesting. It also mentions something about an entirely new Taskbar that has been in the R&D “Lab” since 1999!
Also mentioned was that… “Microsoft is investigating a pie menu-type circular interface, similar in function to the dock in Mac OS X”
Well not to be on Apple’s side or anything, but they’ve had the dock awhile now, but perhaps a circle dock would be neat as well…. I really like the sound of that.