Call of Duty is a huge money-maker in the gaming world. It's got a huge following, and easily beats out all other titles on any console for now. It's the equivalent of printing money for the developer, and Black Ops II is no different. Hitting $1 Billion in worldwide revenue in 15 days, it beat out the previously held record by last year's COD title, Modern Warfare 3 which took 16 days to hit $1 Billion. Whatever these guys are doing, they're obviously doing it right.