Oh yeah, it's finally here...the RC1 edition of Windows 7. I have been running Windows 7 beta on two of my machines including my main machine for several months now and haven't had one issue. MS finally did it right and put out an OS with virtually no bugs in it. I would highly recommend the upgrade to Windows 7 from both XP and Vista. You'll notice increased frames per second in games (I noticed an increase of about 20-30fps), it looks better, and it's more secure. The only negative is that CoD4 won't work on punkbuster enabled servers because punkbuster doesn't yet support Windows 7, but it's only a matter of time until they fix it. Download link is below...
http://www.microsoft.com/windows/windows-7/download.aspx