Frankly, I doubt very much the movie will be any good at all, if it ever comes out. There ISN'T a good way to trim a story of Mass Effect's size down to 2 or 3 hours tops. It'll either be horribly rushed or it'll be changed and no longer be the ME we fell in love with. Lack of Seth Green also doesn't help at all.
I'd still see it, since why the hell not, I guess. I also agree with, as has been pointed out ad nauseum, MY Commander Shepard isn't in this movie. Her dialogue and feelings won't be in it, many of my choices won't be. It'll be a flash in the pan at best (something flawes and that I don't feel invested in but am at least entertained by) and an abomination at worst; from my perspective, anyway.