I just finished this game on the PS3, and it is an outstanding platformer. There are a couple technical problems with the game. For instance there were a couple areas where Ratchet would get stuck and there is no way to get out. I had to quit the game and restart.
Those small problems aside, it was a great game, and I am having a great time playing through it again on Challenge Mode. Once you get the VX version of the Nano Swarmer, forget about it, there is nothing that can stand up to it.