I have a 3D TV and I love it. I don't HAVE to watch anything in the 3D, but I like having the option. Do ALL movies need to be in 3D? Hell no. Yes, it's a gimmick. But it's one I happen to enjoy. I don't get headaches or eyestrain. But I guess I'm in the minority (although I have a feeling that a large chunk of people who _____ about 3D do so because it's the cool thing to do nowadays)
To be honest, I wasn't sold on 3D for the home theatre. But I got a 3DTV for a damn good price, that included a 3D BD player and 2 pairs of active glasses. So I bit, not anticipating actually using the 3D. But then I fell in love. Granted, there's not much content up here (Canada). No 3D channels (save for a preview one on my digital cable that's just a loop) so I'm basically relegated to watching my 3D BD's over and over. But it didn't cost me anything extra (aside from buying a couple more pairs of glasses) so I'm not complaining. As long as I can get the 3D BD's for roughly the same price (sometimes cheaper) than the regular BD price I'll keep buying them.
So am I sad to hear that 3D is probably on the downward slide...? A little. But I think it's in direct relation to how the studios have handled it's marketing and push into the consumer market. Poorly post-converted films, too many (unnecessary) releases, too high a charge for the 3D versions, along with manufacturer exclusives on the retail side, put a bad taste in a lot of consumers mouth. So yes. There's going to be a backlash. I think that's all it is at this point. IF they better handle 3D in the near future they it should stick around for some time.
'Their' biggest mistake was handling it as anything but a niche market. I don't think it has the ability to go mainstream, nor do I think it needs to. But, they saw the $$$ and jumped in head first.