In celebration of the online success of Call of Duty: World at War, Activision is presenting the fan community with a couple freebies this weekend. First, because of the huge popularity of the Nazi Zombies game mode, the Co-Op Nazi Zombies playlist for Xbox LIVE and PSN public games have been unlocked. You’ll now be able to play Nazi Zombies online right away without completing the Solo campaign. Also, this upcoming weekend is a Double-XP MP weekend. Gamers will be eligible for Double-XP starting Thursday, January 15, 2009 at 10:00AM PST.