The problem is these Hollywood douchebags are converting every 2D movie under the sun to 3D ! These movies were not set-composed nor filmed in 3D and the director did not intend them to be 3D.
True 3D movies like Avatar or the 3D animated stuff like Ice Age 3D work very well for the 3D because they were made to be 3D. All these conversions are just ridiculous. Last year Clash of the Titans 3D conversion was panned, everyone said it ruined the experience.
Anyway, 3D is awesome when its done right. The Hobbit in 3D at 48 fps is going to be awesome !!
kpoole the 48 fps might help those headaches. I too have experienced the eye strain from a 3D movie. But I don't think its much of a factor for this decline, Avatar and other 3D films have done very very well. I think its just that these recent movies are not really much different in 3D than 2D, because they are conversions.