Windows XP sucks ass. Sorry to all ye who like it.
XP was my trigger to leave for LInux. When Vista hit, I didn't like it because of the bloat. After SP1, and after hardware moved out of the single-core age, Vista became usable, and even enjoyable.
When the Windows 7 Betas came out, I downloaded them. I'm alternating between Vista Home Premium and Windows 7 RC on my laptop at home right now. I actually went to buy an upgrade license last night, but the $49 promotion ended and it's now costing $119. Fifty bucks for Windows 7 is in my price range, $119 is not.
Compared to Vista SP1, I like Windows 7 much better, but there are still some software issues that have yet to be resolved (big on for me, VirtualBox fails to pass USB Devices property to guess systems) but hardware is great.
The Windows 7 Client is awesome. WIndows FINALLY manages updates and upgrades of third-party drivers; that makes me happy.