BioWare has its hands more than full as it develops its first-ever MMO in Star Wars: The Old Republic, which is estimated to cost around $100 million to develop and market. While Star Wars is a fantastic universe, BioWare's own Mass Effect IP is very rich as well, and Janco analyst Mike Hickey sees a Mass Effect MMO as a great opportunity.
"Looking forward, we believe BioWare could develop an MMO based on their highly successful Mass Effect franchise, which should have a considerably better (relative StarWars MMO) margin profile, given the dilutive nature of the LucasArts royalty," he said.
This certainly seems like a genuine possibility, as long as BioWare can prove its MMO chops with The Old Republic first. BioWare itself has even acknowledged that an MMO in the Mass Effect universe would "make sense."

