Well I've seen it first hand that Vista uses A LOT of memory. I just upgraded my computer to 3GB and it uses more. I'm not sure what the name of that technology in vista is to make it use more memory when you have more memory, but it's definitely working. Here's a screen shot of me using 3 programs at one. I'm at about 1.4GB of usage at the moment of screenshot. How much does everyone use on the average? 
