Superb
Good replayability, good selection of weapons, awesome graphics, a suitable amount of gore, and a definite line between tactics i.e. headshots are rewarded, but you can auto fire, or play it stealthily; the variation is lots of fun.
The challenges and emblams added lots of replayability, as well.
Only one bug - in the bomb defusal section, if you click rapidly on the battery or the wire leading from it, the wire you are supposed to click just jumps to being cut, but the timer keeps going, and the "Mission Complete" screen comes up.
This needs fixing.