Watched this last night. I never played the games, but I knew of them. I knew about the bullet time, and roughly that he kills a lot of people. The movie has a clear cut story, but you never know how everything pieces together until near the end (Which I like, keeps you guessing). I really can't comment on the visuals, it was a decent theater, but the sound is going to set a new standard. Lots of bass sweeps, low rumbling explosions, and well placed details to accent them. This isn't your typical explosion that hits you will all forms out sound at once. It felt almost separated, each different range coming at different times, layering and building up a much more violent and devastating sound. They mimicked the Bullet time almost exactly like that game, with similar sound muffling (Watch youtube clip for reference).
Overall I was very entertained, and drawn in by the dark story and characters. Recommended guy action flick.
Trailer:
Bullet time:
SheepStar