If you're a fan of MMA, you will probably be aware of the Strikeforce Grand Prix this weekend. To celebrate, http://www.trueachievements.com/EA-SPORTS-MMA-xbox-360.htm
will be hosting a double XP event.
The double XP weekend started Thursday morning, and will run through until Sunday night.
With a large number of the game's achievements based on rank progression online, make sure you don't miss out.