Black Ops 2 - I don't say this lightly, and I hate to say it at all as I loved the original BlOps - but BlOps2 is probably the worst FPS I've ever had the misfortune of playing.
I honestly can't understand how they've managed to make a game not only worse than MW3, but THIS much worse.
After MW3 I seriously contemplated NOT getting it, but caved based on the strength of the original BlOps game. Sadly, this is nothing like that, and far more like the other Treyarch games, simply dreadful.
Spawning - awful. I've lost count of the number of times where I've spawned next to exploding cars, into the middle of airstrikes, into direct enemy fire. There's no spawn protection whatsoever.
Head-glitching - How is this still in the game? A constant criticism of MW3, and it's STILL there in BlOps2 - do you NOT listen to feedback at all? Worse still, when I manage to hit them in the head (it must be the head as it's the only part of them showing), I get multiple hit markers! WTF?! How are you NOT dead?
Quickscoping - Another constant complaint. How do Treyarch respond? By making it even easier to do. Genius.
Maps - They're all near enough the same size, where's the variety? No large maps, the only tiny map is a revamped BlOps1 map.
Lag comp - Yet another complaint about MW3, and if anything it's now worse. Playing the game on a fibre connection - might as well not even bother. See opponent first, fire first, dead first. Absolute b0ll0cks.
Hit detection - You can see how poor this is in the killcams. If you hipfire, close misses randomly register as hits. The worst one I saw though was someone's final kill killcam, where the bullet actually hit the rifle butt of his secondary weapon that was on his back. Somehow, hitting that killed him. Seriously you couldn't make this sh*t up.
I'm now back on BlOps1.