This has me excited. Nay, this has me most excited. A few days ago at E3, Valve revealed new details of the up-coming Portal 2. Some of it didn't matter to me (good for them that it's coming out on Playstation 3, but I don't have one, so meh). But after watching some videos of people trying out the new abilities and puzzle pieces, holy cow, am I excited.
Here's a video from G4. Pay attention to what the talking heads have to say, but especially pay attention to what the video is showing.
What has me interested is the co-op play. I've never really done that before, but I have a few people in mind that I'll be arm-twisting in 2011 when this thing goes gold, especially since it'll be releasing for Macs as well.