I'm loving Windows 7 for about a month now...
In comparison, Vista only lasted on a PC for 4 days before being swapped out for XP.
7 is everything Vista shoulda been.
As for the taskbar, I think it's great -- for some things like Trillian/ICQ (multiple windows, unless you use tabs) it takes a bit to get used to - but overall, I'm sticking with 7 over XP
Running Windows 7 Enterprise 64bit on a Core2 Duo with 8gb of RAM