-If you zoom to snipe from distance on multiplayer, the fps drops to about 2 or 3, wtf, CoD and Halo:Reach are buttery smooth, always. (it seems like the enemy player is the only thing that drops frame rate, if you move your screen the map moves smooth)
-I fell through the map in campaign and had no way to get out! at all! Stuck in water swimming in a virtual 'box'.
-I finished the campaign on super soldier, it even says 19/19 and i didnt get the achievement -_-.
-I direct headshot snipered an enemy on multiplayer, he was standing still uncloaked looking around, apparently it missed, im 100% sure it didnt miss however, and he turns around swaps guns and finishes me off as now i am screwed with a handgun or sniper with him charging at me.
-half the time you go to stealth kill an enemy it doesnt register
-Migrating session bs.
That is a pretty substantial list of heavily game reducing problems. Absolutely frustrating for a game which wasnt cheap.