Call of Duty Online was announced by Activision when the company first stated their interest in an Massively multiplayer online game (MMO) in early 2011. By then, it had been in development for two years. Call of Duty Online is free-to-play for mainland China and is hosted by Tencent. Since Activision had lost the publishing rights to Call of Duty and several other franchises in China due to a legal dispute on most of the Western gaming consoles (Xbox 360, PlayStation 3, and Wii), it had been rumored that it would be Microsoft Windows-exclusive, since PCs hold the dominant share of gamers in mainland China.
Call of Duty: Modern Warfare 2 is the sixth installment of the main series. It was developed by Infinity Ward and published by Activision. Activision Blizzard announced Modern Warfare 2 on February 11, 2009. The game was released worldwide on November 10, 2009, for the Xbox 360, PlayStation 3 and Microsoft Windows. A Nintendo DS iteration of the game, titled Call of Duty: Modern Warfare: Mobilized, was released alongside the game and the Wii port of Call of Duty : Modern Warfare. Modern Warfare 2 is the direct sequel to Call of Duty 4 and continues the same storyline, taking place five years after the first game and featuring several returning characters including Captain Price and "Soap" MacTavish.