PixelJunk Eden is one of my most anticipated games for the year so I was super psyched to see the demo up last night; I hadn't heard anything about the demo being announced.
I've been playing around with it quite a bit (two levels available); I'm very, very impressed with the game so far. I was sort of afraid it would be much more esoteric experience since people seemed to have so much trouble describing the game. It's really just a 2D platformer with super cool mechanics, very stylized graphics, and a fantastic soundtrack.
All PS3 users should go check it out ASAP.