Alright, I figured I wouldn't get into a discussion regarding the game's graphical prowess, but either way... I don't agree, I haven't seen anything from R3 which I think couldn't have been replicated in the Uncharted or Killzone engines. Please point to a R3 video where the number of enemies on screen outshine any of the other games (I'm honestly curious). KZ3 in particular have some setpieces with A LOT of shit going on, so I find it unfair to state that R3 is much more expansive in its scope.
Effects-wise, the game looks good, but not good enough to warrant the drop in resolution since KZ2/3 managed to implement fantastic object-based motion blur without destroying the IQ (KZ3 even has MLAA).
The framerate in the single-player portion of KZ3 was generally very good, and I'd put it above the things I've seen from R3. I know the leaked R3 boat demo is old, but when it can barely sustain the framerate in that level (which is very small scope-wise), I wouldn't use the framerate as some kind of plus point (just yet). The recent R3 footage of the robot-spider fight also had middling framerate, especially when the robot blows up.
No tearing has been a staple in Sony-exclusive games as of late, so it's to be expected of this game too.