Even when done well, and I suppose Avatar is the gold standard, much of the time the 3D effect creates artificial depth that detracts from the sense of realism. Of course, Avatar wasn't intended to be particularly realistic, but even the interior scenes in the various labs and spaceships seemed very unrealistically stretched in the third dimension. It became quite distracting and annoying. Yes, gee whiz, you can make objects appear at any depth, but just because you can doesn't mean you should. There are times when they really should turn it off or tone it down a lot. I never got the sense of subtlety in the 3D effects, they were always in my face. Like music that goes from loud to loud to very loud.