Left 4 Dead

I just finished playing through the Left 4 Dead demo with 2 friends and immediately afterward, pre-purchased it for $45 through Steam. I also finally got Audiosurf for $2.49. It was just an amazingly fun experience. The number of times either "OH SHIT" or "OH FUCK" was screamed was ridiculous. Killing zombies was very much satisfying, but the only problem is that when playing without 3 other people, the remaining characters will be AI controlled. There's nothing else to indicate that this game will be anything less than awesome, so definitely check out the demo, also available on the 360, if you haven't already.