Do people want to buy a new Call of Duty game every year? Yes, apparently they do. Treyarch announced today that Call of Duty: World at War has sold 11 million copies worldwide since its November 2008 release.

WaW seems poised to overtake its predecessor, Call of Duty 4: Modern Warfare, which was released a year earlier and has racked up 13 million sales to date. The increase in PS3 and Xbox 360 owners between 2007 and 2008 no doubt fueled the growth of the COD customer base. There's another factor at work here, though: WaW had Wii, DS, and PS2 versions while COD4 was only on the PS3, Xbox 360, and PC. Platform-specific sales figures weren't provided by Treyarch so it's not clear how much those three extra versions contributed to the total, though.

Modern Warfare 2 will be released on November 10th, 2009 and it seems like it's only going to be hitting the PS3, 360, and PC. Activision hopes it will be the best-selling game of all time. Will they be able to achieve that goal without the Call of Duty prefix and without the hefty user bases of the Wii, DS, and PS2, though? We shall see.