From the company that brought you Flow and Flower (which was also fantastic).
If you have a playstation+ account, you can get it now. Everyone else has to wait until next Tuesday. Its currently charting a near flawless score on Metacritic, and deservedly so.
I would try to describe it, and why you need to play it, but that would just ruin it. It's perfect. Its Shadow of the Colossus meets Nights Into Dreams. The two player mode is... something else. And I'm going to play many many more times. And make friends play it.
If you own a PS3, you owe it to yourself to get this game.
It is that simple.