I've always seen very little difference, but I've always felt that's because graphics mean so very little to me after a certain point. I really couldn't care less if a good game is 720 or 1080. I would actually prefer 720 if it cut down on stutters or improved frame rate/slowdowns.
Graphics are the absolute lowest tier on the hierarchy of what makes a good game, so it's pretty sad that people will make such a big deal of it. That said if I can have better visuals for the same price/effort and without compromising other aspects, sure I want the better package.







