Having played the CoD games since the beginning on both PC and console, I have to say that this release blows my mind. It's actually quite revolutionary compared to the other releases (CoD3 being quite good in its own right), and this is seen not only in its graphical content (which is brilliantly presented) but also in the cinematic effects, story, and bonus features (arcade mode is a fantastic touch to an already great game). The power of the PS3 isn't really harnessed since I think this is a port, but even so the graphics are definitely going to be hard to beat on any platform. Online gets a "5" too- it is an amazingly fun addition to the game. Coupled with LAN party capability, split screen, and (as I said already) arcade mode there are hours of game play to be found here.
In its single player mode the game is no less of a beast- it is a little short, but the difficulty levels make up for that and add some longevity. I don't want to spoil the game for those that have yet to play it but one of the levels finds you thrown out of a chopper after a tactical nuclear weapon is let off during your extraction. The graphics and atmosphere here were nothing short of breath-taking. This game has guts and it's hard to find much wrong with it at all.
I would recommend this to all PS3 owners- it will no doubt be the standard for FPS for some time to come.