EA has put a "Mass Effect 3 Mission Command" app on Facebook, through which fans can unlock some Avatar items and possibly get chosen for early access to the game's upcoming beta. There's also a big sweepstakes opportunity to win one of two custom Xbox 360s, painted in the game's Paragon and Renegade themes. EA sent us these pictures earlier today.
[UPDATE] Big props to commenter LeetEmu for noticing that "Renegade" is in fact misspelled on the image supplied (drive slot). Wow. Hope they fix that, pronto.