Well I just finished installing 7 on my laptop (Dell Latitude D600 - 1.6 Ghz Pentium M, 2GB RAM, ATI Mobility Radeon 9000) and I must say I'm quite impressed. I had a spare laptop HDD in a caddy already so I just popped them out. The setup took a little longer than expected, but hey, it is a beta after all.
First off, I'm impressed that it automatically loaded a driver for my internal wireless card. I was able to connect to the internet right away and install some updates. I also like the new way the connection manager is set up when your not connected - it opens upwards instead of opening a whole new window. Haven't done too much more, so I'm gonna poke around some more.