I don't think it's an incredibly huge deal. Yeah, he looks like an idiot, and someone should have taught him how to bow and still preserve some sort of dignity at the same time, but I don't think this particular action is going to lead to the end of the world. A bow I would have been ok with; this looks more like a submissive bow.
He's on the same path as Bush Jr, piling up "whoops"es and "can I have a do-over"s while he turns out to be just another joke of a President. At least Bush's excuse was that he had the IQ of a donkey. What's Obama's excuse?