I reviewed it when it came out, I thought it was fine, but the strength is more in the story telling of the cutscenes than the actual game play.
The game itself is pretty repetitive and once you get a feel for it, it's actually a little dull.
Levels are either a) in daylight or b) in the dark, and either c) against the infected or d) against militia groups.
So if your currently playing in the daylight against militia groups, the next level will be in the dark vs. infected, and then it alternates.
The story is top notch though.