Well I sat down a couple weekends ago at Best Buy, put on the 3D glasses and watched about 10 minutes of the demo "Monsters vs. Aliens."
Within half an hour, and every day after that for over a week, I had a nagging headache that lasted most of the day, one of those where you feel like the back of your eyeballs is being squished in a vice.
I wonder if the two things are related somehow. It could have been the relatively small size TV they had in the demo area, or the fact that directly behind was a wall of other TVs that were reflected in the image I was trying to view.
I am very excited about this technology, and want it to be as good as what I've experienced in the movie theater, but if it causes headaches I will have to pass.