Mass Effect 3 won't just bring Commander Shepard to Earth. He/She is going to Mars. Briefly, according to series writer Mac Walters, during an interview last night with Game Trailers TV's Geoff Keighley.
Check out a short glimpse of ME3's Mars action in the video below, which contains the entire Mass Effect 3/Modern Warfare 3 episode of GTTV from last night. The Mars stuff starts at the 5:58 mark.
There's also a lot more talk about the game's co-op mode. You'll find that at 14:50.
GTTV, January 20, 2011 [Game Trailers]