I'm considering whether to upgrade from Windows XP to Windows 7. IMHO, the new OS seems to be not sufficiently "mature" yet, and it is better to wait for the first service pack to come out before actually upgrading.
As Cybercore stated, an Upgrade Install is crap. Clean install is the way to go. Especially when going to a completely new OS.. Not to mention a direct Upgrade from Windows XP to Windows 7 is not available anyway.. That is to say you actually HAVE to Clean Install the new OS if your going from Win XP to Win 7...
I would say that Windows 7 is definitely mature enough and was at the time of release for that matter... I think you should go for it.. Just make sure to back up all your personal files before making the change.
If you run into any problems during the installation, please feel free to post them and we'll gladly help you out..