Romney "won" in the sense that he came to the debate more prepared, energetic, and didn't do anything exceedingly awkward. Obama "lost" in the sense that he seemed bored, tired, and too long-winded.
Substantively, Romney just waved his magic wand and white-washed every hole in his supposed plans. Obama attempted to point these out and share his own solutions and accomplishments, but failed to do so in a clear or cohesive manner.
Weak debate all around. Romney should have been the one on the defensive, but benefited from his willingness to bend the facts, and Obama's apparent lack of desire to be there. I don't know if it will move any polls, but it's definitely going to help Romney more than it's going to do anything for Obama.