I completely agree with you. 3D is only worthwhile for Avatar... and Gravity.
Gravity has more going for it than pretty, but the 3D helps give a sense of distance in space. It was well done and not obnoxious like so many other movies. Before Gravity there was a 3D preview of The Hobbit part 2, and the 3D looked horrid. Gravity though didn't make me keep thinking about the 3D, it just felt natural. That's not something I've really experienced before.
Anyway, it's well worth seeing in 2D as well, to be sure!