That interview has me So Pumped.
Really, my favorite thing about Mass Effect is that it feels like a very much fleshed-out universe. The lore behind Mass Effect 1 was so incredibly deep and satisfying that I couldn't help but admire not only the narrative but the history, everything about the game felt like it had been built on hundreds of years of stories and adventures.
I spent hours reading about their FTL technology, how humans had reacted to the martian technology and the discovery of sentient alien races, even about how their damn guns fired. More than any other game (and probably most sci-fi movies, too) Mass Effect felt like a universe that had been grown long before I picked up the controller, and I'm really glad that they seem to be expanding on this tenfold for the sequel.