I'll add this too.....it seemed to get stuck on processing the data. I'm not sure if it was a bug in reporting progress back to the user or what....either way, it was an annoying upgrade.

I upgraded my dual core laptop 2GB of memory from Vista to Windows 7 last night, and I can say it was a very slow install! It took my computer a couple of hours to upgrade from Vista to Windows 7. Microsoft should be ashamed to release something that slow given their resources and money. I'm also a Ubuntu user and I have been very impressed with upgrade and install process there. Microsoft has to do better if they expect people to pay for their software and OS.