I've played it briefly when it came out, stopped, and haven't gone back to it since. The graphics are pretty unexceptional - I think HL2 looked better, though it's hard to say given the completely different visual style, but regardless, given that my PC can run stuff like Oblivion or FEAR with high-quality graphics, I was less than impressed.
The physics are nice, but you end up doing so much of kicking people into spikes / pushing people off of ledges / breaking support beams to drop crap on the enemies that it very quickly ceases to feel like anything special. (I was very nearly bored with it by the end of the tutorial...)
I'd have spent more time on it, but the load times are simply horrendous - literally the longest I remember seeing in a FPS game, ever - and after getting killed a couple of times in a row, I just said screw it, quit, and started to play Marvel Ultimate Alliance while waiting for NWN2.
