I've been on Windows 7 since beta (first Microsoft beta I've tried that didn't crash once) and I'm pretty happy with it. The taskbar management is deifnitely a step up (with all of the software I have open for my job, and still being able to fit on one row, was impressive).
I havent looked at too many Linux GUIs in years (about the time KDE 2 just got released). As for comand line based systems (I have a few servers running CLI only), I love Debian.







