Infinity Ward by far. Why? Modern Warfare 2. Why not Treyarch? Because other than Black Ops 1's campaign, Treyarch's Call of Duty games suck. World at War is overrated and terrible and I hate world war games, anyway. Black Ops 1's multiplayer is unplayably broken, Black Ops II is also broken but has the best graphics of any Call of Duty game ever. But it has terrible incoherent campaign mode with a stupid multiple endings gimmick that no one cares about and focussed on a campaign mode no one cared about and didn't bother doing anything with the multiplayer. Just stick in some new guns and done. At least Ghosts has a few added features, Black Ops II doesn't even have that. It just centres on Zombies mode which sucks. And Treyarch's Call of Duty games are shit. I can't wait for Call of Duty Ghosts.