Great game, perhaps a short-ish campaign (still about 8 hours on normal more if you look for journals) does not ruin the fact that it plays superbly. You'll love every minute of it or there is something wrong with you. Dark, gritty and tough, try playing it on Superhuman and beat it that way. A great game and hopefully not the end of the series.
The best bit is playing split screen co-op. If you want a 2 player shooter, this is it.