It's an artistic style type of game with minimal gameplay and story elements, but with that simplicity they just made something... so... AWESOME. Also, it's about a Journey. It really is.
http://www.youtube.com/watch?v=J-W-WvskODMAnd you could always watch a Let's Play to get a little bit of the experience, but really, to do it yourself and to interact with another person without being able to talk to each other... It's crazy how well they designed it.
It becomes surprisingly intimate without the get into your pants type of deal. :3
'Course, as many people warn, if you're into head shots and high scores, this game ain't for you. For me, I've completed it six times.