There are a couple of things to keep in mind here. One, Eidos Montreal took on Deus Ex, a project fraught with risk, and nailed it. Human Revolution was a proper, full-on and entirely satisfying DX game, and that buys the studio a LOT of credibility. Two, as others have mentioned, the look is less important than the man, and the man will be dependent upon The Man - Stephen Russell. I'm willing to put up with a lot, but if Stephen Russell isn't back on board it's going to be a problem. Remember when Rockstar first announced that it wasn't going to use James McCaffrey for Max Payne 3? Leaving out Russell would probably be even worse. A Robert Smith-esque Garrett I can handle, but the real test will be when the cast is announced.
I'M NOT FREAKING OUT
I'M NOT FREAKING OUT