It's a great game no doubt, excellent graphics, the multiplayer graphics are especially impressive (considering how seamlessly they run).
Personally I'm not a huge console FPS fan. I was raised on pc FPS (TFC especially) in that sense the pacing of the multiplayer is a little slow for me. The controls felt a tad sluggish to me (and to many others for that matter). When questioned on it, Guerilla said it was an intentional design choice to make your character feel "heavy" as you are large, bulky, and carrying lots of gear. Personally I didn't buy that, I play games for fun not realism. When controls feel sluggish, it hinders the game for me, especially when I'm used to the speed and precision of the keyboard/mouse.
I heard they had patched the controls to make them feel more fluid and responsive, and but I haven't played for a few months. I went back to playing TF2 and L4D on PC. I'll pick it up again some time, as the multiplayer in principle was excellent. The unlocks were a little tedious to unlock, but some people like that feeling of character progression. Myself... I prefer everything to be unlocked from the start. The maps are good though, the graphics are solid, the gameplay (minus the semi-sluggish controls) was excellent as well. It's deffinately a buy if you have a PS3.
I just wish more people on the PS3 used their headsets. Sony should really consider throwing in a blue-tooth headset as one of the accessories in the console package. I think it would greatly stimulate their online experience.