As the game gets closer and closer to release, we’re releasing more details, and thus I’m linking them. This article, also from GDC, includes the following video with gameplay and cutscenes. For GDC there was little to no music, but you can hear the high quality sound and voice-acting. This is the game I play 8 hours a day, 5 days a week.
P.S. This other article here is an interview that has some more details about Mass Effect 2 for you Mass Effect fans!