I put the new Windows 7 Pro on my work laptop today (Dell Latitude E 5500), and was very impressed in how well it works. The laptop seems more responsive than it did with Windows XP.
I have been using Windows 7 RC1 on my home computer for about 3 months now, and it has been pretty solid. I will continue to use it until the RC runs out June 2010.
My favorite feature is the Windows XP mode, where I can install older programs that won’t work with Windows 7. Cool thing is that after you install a program to the virtual pc, it shows up on the Windows 7 side as well.