Well, I think we both agree that ME3 will not have MP. So I don't think we have to worry about them screwing up the single player because they're dedicating too much time to a multiplayer element.
I'm thinking it will be a spin-off game. They say that ME3 is the end of Shepard's story, I doubt they take any of the focus off of it.
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TheRock ~ Death By Misadventure, Not Suicide
"Would've liked to see that." - Ayuyu on my boner