I have win 7 on a Toshiba and it's working good so far (but i am a very counscious person - I don't install crap, don't just NEXT-NEXT on anything, I clean the unecesarry temp folders, caches, useless files like the update cache for windows monthly, also I have only the needed services on, I even keep RPC and BITS off and turn them on only when I want to run an update)
I run Windows 7 Starter on my HP Netbook and love it
I run Windows 7 on my desktop and love it.
I ran Windows 7 on my HP DV9700z and there were no drivers for it so I didn't love it (but thats besides the point).
Windows 7 Pre-installed from HP seems to be good!