You can play Modern Warfare 3 multiplayer right now—sort of
Fans looking to try out Modern Warfare 3 multiplayer again ahead of the Nov. 10 launch can do so in-game right now—and there’s nothing illegal or frowned upon about it.
Included in today’s massive 100 GB-plus update for Call of Duty is MW3’s multiplayer pre-load, meaning all of the files for the new game’s online component can be found in the game. This means MW3’s multiplayer is playable, but only if you’re offline.