The Call of Duty: Modern Warfare II open beta will run for two weekends; the first will be exclusive to PlayStation consoles from September 16 to 20, and the second will be available on Xbox, PC, and PlayStation players from September 22 to 26.  If you preorder the game for PlayStation consoles you get exclusive access to the beta on September 16 and 17. All PlayStation players can then join in for free starting September 18. Players who preorder on PC and Xbox can join the open beta on September 22 and 23, during which time it will remain available to all PlayStation players. From September 24 to 26, the open beta will be free to play on all platforms. You can find a simplified schedule below. Call of Duty: Modern Warfare II beta schedule September 16 to 17: PlayStation preorders only September 18 to 20: All PlayStation players can play September 22 to 23: Xbox and PC preorders, along with all PlayStation players September 24 to 26: Open beta is free for players on all platforms