The 3D stuff is really starting to annoy me. I'll always go to a standard showing unless the scheduling doesn't work out. The scenes where it is so blatantly obvious that they were designed for 3D really bug me. The couple times that Cap through his shield directly at the camera? Really, is that necessary? If they're going to use 3D, please come up with better ways of utilizing it instead of just going for that wow factor.
And since you mentioned the spiderman trailer, I assume those 3D sequences you mentioned are the ones where they show his point of view while swinging through the buildings. I hope that's a 3D thing, because it looks really cheesey if it's not. I'm going to get turned off by that movie really quickly if there's a ton of those shots, especially since I'll avoid a 3D showing like it's the plague.