i’m running a couple of my main windows 7 laptops (and a netbook) with only 1 gb of ram and it’s running great, but for a system that 1) allows for additional ram 2) has shared video memory and 3) might run xp mode at some point, 2 gb of ram is really nice and very inexpensive.  i just recently upgraded two laptops to windows 7 rtm for my cousins and these had 768 mb usable memory.  i wish i had more time to do some performance testing on 1 gb vs. 2 gb, but for $50 both will run nicely this fall.  i’ve queued quite a few installations, so i’ll continue counting the rtm installations – i’m up to 7 installations.