Cameron's got a big ego but zero pretension, so when he holds back on saying that the film will be revolutionary (but that the techniques used however are revolutionary) he is not playing down his movie, he's just being scientific, i.e. let's wait till we see the data. What he knows for certain, again scientifically, is that we will be blown away by some of the shots in the film, because it even made them go "this is ridiculous!" upon receiving finished shots from Weta.

Personally I think Cameron is one of the few people striving to push the medium forwards, and he's using sci-fi to do it, as is often the case with such progress.

IMAX will become irrelevant soon anyway, because digital cinema technology will overtake it in the resolution stakes, all cinemas will have the IMAX resolution capacity, and the big movies will be in 3-D, so people are going to want to sit closer to the screen to see farther into the "window" of the 3-D film format (the 3-D-ness expands out as you get closer to the image). IMAX has woken more people up to the coolness of getting right into the picture, even on non 3-D pictures like BATMAN:TDK. In the long run it's the theater design that doesn't allow anyone to escape a titanic portal into the movie world that's unique to IMAX. It's too bad for Cinema goers sitting at the back in a theater with a 32K projection of a 3-D blockbuster (I'm imagining Forever War from Ridley Scott) they just don't know what they are missing. But then again, I hope the traditional cinema design goes away so everyone gets an immersive experience. If you want to sit back and make out at the back of the cinema or watch your iphone, just use an LCD TV (I've never seen someone using their mobile at IMAX).

I don't think 3-D is a gimmick. Many filmmakers were reluctant to change to colour after it was introduced in 1927; there are industry figureheads who called it a fad a year after it went mainstream. There's nothing inherantly whiz-bang about 3-D; it just removes the need to infer depth from a screen, which is actually hard work - try closing one eye for a while and see how your perception of depth is affected. I watched Monsters Vs. Aliens, and I noted that it was not even apparent that it was in 3-D, because after the initial suprise that the screen has apparently vanished, you relax into the reality of the stereo space - just as familiar as real life. I think it's a progression like any other in cinema - like the introduction of colour: we see, and we see in colours; we percieve with two slightly different perspectives which are fused into one image by our brains.

Anyway with the new fusion camera systems, you've got hand-held rigs and you can even reduce the interocularity (distance between lenses) of the stereo image down to nothing, i.e. one lens effectively. So the perception of depth becomes just another tool like depth of field, that the filmmaker can use according to his taste.

I do wish that we didn't need to use glasses to get the effect though. But apparently there's already a couple of prototype solutions to that problem.

If this is stereo like U23D or Beowulf at IMAX, then I'm stoked. There are a few right-out-at-ya! moments in MBV3D, but for the most part you're not even aware that it's 3D, it's just more like real life because you're not looking at a flat image anymore - the screen disappears basically.