I got it on release day and played with it over the weekend. I am a software developer, and I also tested Vista from Longhorn through RC1 phases. I was going to put Windows 7 on my primary system to replace XP, but here is my take on it.
Look and Feel: Similiar to Vista. Feels considerably more responsive on low end hardware.
Ease of install: Fairly simple as far as steps, but the 32 bit version kept crashing on me. Took about 10 tries to get it to take.
Stability: This is why I won’t put it on my primary. It seems to crash and reboot a lot.
System: 1.5Ghz Via C7 based x86-32bit system. 1GB DDR2 ram, integrated (read: no) video. I don’t know if the Via CPU may contribute to the stability issues. I’ve had no problems with ubuntu on it, however gOS was also a pain to get installed (although I wouldn’t recommend that operating system to anyone).