Like Diablo and Starcraft have separate development teams, the same goes for Dragon Age and Mass Effect. Dragon Age is from the old school Alberta camp and the character models make the game look suspiciously like a derivative of the Aurora engine. Mass Effect used the Unreal 3 engine.
Dragon Age ditched quite a bit of graphical polish in an effort to focus more on story and gameplay to be more in-line with Bioware's older RPGS (as the developer's claim, anyway). As we all know, Mass Effect was little more than a 10 hour game if you removed the aimless Oblivion-esque horse riding side quests (aka Mako).
Of course, we'll find out of DAO actually is a much more complete game than ME, or if they were full of it and it was just an euphemism for "we had a small budget."