Bought it, Beat it. The day it came out, I just couldn't put it down. It's amazing, quite possibly the best game I've ever played. The story is awesome, the character voice acting is great, really funny and clever at times, the attention to detail is CRAZY, and probably my favorite part was the mini cut-scenes.
All the time while you'd be playing along normally, something crazy just happens. It's so fluid that you can't help but love it. An example is right when you start the game, you're climbing a train that's hanging off the cliff. You spot your path and start along it. As you're scaling up the yellow tubing on the side, all of a sudden it breaks off and slams you into the side of the train. It just makes the environment feel so alive all the time.
So yea, if you have a PS3 and you don't buy it, you're a fool.