User blog comment:Crazy sam10/Call of Duty: Ghosts Teaser Trailer released/@comment-2228158-20130502014513/@comment-4921618-20130502035224

They actually update the graphics every game. It is always advanced to the previous. I don't remember Call of Duty 1 having the same graphics as Black Ops 2. And for realism, Modern Warfare 3 and Black Ops 2 are both very different in graphics.