Mass Effect was written as a Trilogy from the very beginning. I can't imagine Microsoft being so stupid as to leave ME2 and ME3 completely off the table when negotiating exclusivity on ME1. Perhaps MS is that stupid, but I'd be willing to bet there was an "option" on that contract that still stands.
Unless EA and MS come to some terms on that "option" -- whatever it was/is, it will remain an enforceable contract as EA can't just dismiss legal contracts entered into by Bioware before they acquired them.
I guess we'll see soon enough.








