*this might shock you all*
For the past week or so, I've been using Windows 7, via the BootCamp utility on my new iMac (27" Late 2009). I've not, for the whole week, booted into Mac, and my MacBook's been in it's case the whole week, for once I've been emerged in the quite pleasing running of Windows 7, on a computer I treasure more than a lot of things.
My basic review of Windows 7 is, I like it, but I wouldn't use it everyday, there's just something about the feel of it which put's me off, this might be because I use Mac OS X all the time now, or this might be because of my roots back to Windows 2000/ME/XP. The taskbar is EXTREMELY big for it's size, but that might be the 2560x1440 display (yes I did have trouble getting Windows to work with the resolution, but I fixed it easily with some driver swapping and configuration).
The compatibility with my Apple Keyboard is ok, but some issues with the Magic Mouse are resolved by using my old Mighty Mouse. Overall, compatibility is good, but I would prefer if it was more supported from Apple's side, as Windows 7 looks incredible on such a huge screen with a resolution to match it.