Ratchet doesn't feel like much of a platformer. It never has. If you are really trying to find the PS3's platformer you are going to need something with a lot more platforming elements and a lot less action/shooter elements. Mario is all about crazy unrestricted platforming through unimaginable locations. It's platforming at it's purest, and yet constantly evolving. Ratchet takes out some of those platforming elements to add in action shooter elements.
So to me, if you are looking for a platformer, there is really nothing that can deliver the feeling you get from Mario's incredible style of platforming except Mario itself. Ratchet is a unique and fun game itself, but if I want a platformer I'm playing Mario not Ratchet. if I want some action packed really fun guns and some decent platforming mixed in here and there then I'll play Ratchet. They just aren't a comparable type of game and in platforming nothing is comparable to Mario.
