http://www.totalvideogames.com/news/Microsoft_Strikes_Mass_Effect_Deal_With_EA_12754_7351_0.htm
"As the Bioware RPG is confirmed for a Spring release on PC, EA announces that a publishing deal has been struck between them and Microsoft..."
"EA has today confirmed that Mass Effect, released last year on Xbox 360, will be heading to PC this May...but not by Microsoft Game Studios. Instead, publishing duties will be taken over by Electronic Arts, adding further clarification to MGS boss Shane Kim's comments yesterday to MTV. "
Kim mentioned that "From a platform perspective, is it the most important that Microsoft Studios publishes it or [rather] that it's exclusive to the platform? That's the way we have to think about it."
From what Kim says, it looks like EA will receive publishing rights for Mass Effect but the game will stay exclusive to the 360/PC
Overall it might be or might not be a good deal for MS corporate, but it does help out guarantee a new exclusive IP for the 360.
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