I was helping a friend set up her Win 7 system and the durn thang hung 4 or 5 times while we were working. I had the feeling we were working with Windows 95 except that there were no out-and-out crashes--but we had to keep shutting down and rebooting to keep working
I can't say I was favorably impressed--however, keep in mind that we were
just setting things up and I was only working on it for a couple of hours, so I have rather limited experience with the new OS.
I 'spect I'll suffer along with Vista for a while yet till they work the bugs out of Win 7.