I got my 20" last Friday - I ordered it the day after it was announced w/ 1GB ram BTO. Ooh its pretty and very fast, at least compared to my ancient powerbook
PhotoBooth is probably the coolest useless app I've used, and definitely kept me entertained for a while. Front Row is actually more useful than I expected .... although the dorm room situation is very conducive to that sort of thing
Add in the DivX quicktime components and Front Row really becomes the local attraction..
Edit: I forgot to mention, I had a problem with the built-in iSight at first. Any images that I took came up all green, even though there was plenty of ambient light and the green iSight-is-on-light was glowing. iChat, PhotoBooth, Account photo, and iMovie didn't recognize anything but a solid color from the iSight. I ended up shutting the machine down for about 10 seconds and then turning it back on - it worked a treat. Restarting didn't work. It hasn't happened since, so I'm hoping it was just a one-time fluke.