I enjoyed Avatar, but after any sustained period watching 3D through glasses I get a mild headache, and I believe this to be quite common.
TV, as opposed to PC is a 'lean back' experience, and anything that is hassle loses utility fast.
Also it is not child friendly...
My home has slightly more tech than the average, but you have to assume that the glasses will get ingested into the morass of Lego, USB memory sticks, magnets, books, action figures, papers, marbles, etc that characterize the habitat of kids.
They are also pretty fragile, and anything that wants to live in our front room has to be able to survive being sat upon.
So glasses aren't a capital asset, but a consumable, I can see me paying $100 per month in replacements, which seems an expensive way to make my life more hassle.