Worst case scenario - This is another Stark clone (you *know* he has Steve's DNA somewhere). Well, it probably could get worse, but that'd be pretty bad.
Best case scenario - Not only is it the real Steve, and handled well... but since he was dead for the whole Mephisto/OMD mess, he REMEMBERS and helps Peter remember... and once Peter remembers, you know he'll be out to fix things. Too bad that won't happen. :/