If there's a gamer in your house, chances are that a game called Call of Duty: Modern Warfare 2 is on his Christmas list. Maybe you've even bought it for your young'n already: the game grossed $310 million dollars on its release day, November 10, and earlier this week passed the $550 million mark. But before you wrap it up and put it under the tree, do you know what you're actually buying? [more]