3D won't last. Its too expensive and not that impressive. Who wants to drop 2-3 grand on TV and still have to buy pairs of glasses that are like 150-200 a piece to watch it in 3D. If you have a big family, you're screwed. 4 people alone would cost 600 dollars just for the cheapest pair.
I don't really see the point, whenever HD TV's became huge and were so expensive, I got it. The quality was so much better. However I just don't see the point of 3D, it isn't impressive enough to get me to buy it. I don't mind it being something unique every now and then, like watching a 3D movie occasionally. I wouldn't be interested in shelling out extra for that though.