The 3D does one important thing for me. It makes complex action sequences, or scenes with a lot of visual noise, more easy for my brain to parse.

One of the problems I've had with action films is the inability to tell what's going on during visually complex scenes. Film directors have been trying to "push" this envelope as action movies have become more advanced in recent years, and in many films this has crossed some kind of a line in my old addled brain.

The 3D gives my brain more data to help parse the onscreen information, and lets the directors push that line a little farther without losing me.

Of course, this just means they'll push it more...