Our most humble of hosts on this here corner of the Intarwebs commented in Dawn's Avatar rant that Avatar could be the Jazz Singer of our time.
Similar themes have been voiced during the run of this inconceivably popular movie. It's going to change movie-making as we know it! It's a technological leap forward!
At best, Avatar is evolutionary. It introduces new methods of motion capture, 3D technology, and possible the most important tool for the filmmaker - live view. Cameron and the crew were able to view a rough cut of every scene as soon as it was shot. Effects, graphics, etc, applied moments after he yelled "cut!"
But will it change movies? Will they all be 3D, mo-capped, computer-generated worlds? No. Sure, for the next season or two, every big-budget blockbuster will be re-done in 3D, but it's too late to film most of them with Cameron's tech, and that is a key component to why the 3D worked. By the time the movies that DO license his new-fangled gadgetry are made and released, the world will have remembered that just because a movie is in 3D, doesn't mean it's worth watching.
Plus, not every movie will have a $200 million+ budget to do this with. Cameron pulled it off because he had Titanic behind him. He was allowed a risk. Now, with another $2 billion in the bank, he can pretty much do whatever he wants. That doesn't mean Jon Favreau gets to do The Avengers in 3D mo-cap.
Look at a few other "revolutionary" movies from recent history - The Matrix and Toy Story. The Matrix gave us that 3D panning effect. It was TOTALLY AWESOME when we first saw Trinity leap up and kick some ass. It was played out completely within 2 years. Why? Because every movie in the world used it. Something explodes? Freeze and pan around it! Jump to light speed? Freeze and pan! It was gimmicky and is now rarely seen.
Toy Story showed everyone that a CG movie could be good. Pixar has a pretty solid track record since then. Even their movies I'm not fond of (Cars, Wall-E) are still full of heart and technical wizardry. How long did it take for the rest of Hollywood to catch up in quality? Well, if you forget about the first Shrek, it finally happened last year. That's 14 years before the playing field was Pixar vs a bunch of really terrible CG animated movies, made simply because studio heads thought it was the CG that made the Pixar movies popular, not the quality stories and directing.
The Jazz Singer rapidly turned what was largely a silent medium (there had been synchronized sound films before it) into a multi-media experience almost overnight. Within a couple years, silent film was dead and everything had dialogue. Hollywood never looked back. For the technology of Avatar to have the same effect, it would mean the death of traditional filmmaking. That's just not going to happen. The risks are too big to make on every movie. The bankable directors are too smart to use the technology uselessly (even Michael Bay still prefers real explosions and stunts over CG). Sure, it will creep in to some enjoyable flicks, but what's far more likely is a bunch of useless 3D-as-an-afterthought, and terrible, TERRIBLE CG mo-cap films that try to cash in on the gimmick.
I remember Cameron saying how he wanted Avatar to be a good 2D film that 3D added depth to. He succeeded in spirit - the movie doesn't NEED the 3D to be viewable, but it's not good. Sadly, most of those rushing to the tech will make movies that fail completely on a 2D level, just the audience can have buckets of blood thrown on them while they duck flying axes.
And between those? A bunch of movies that will ignore these tricks completely. And they'll greatly outnumber the others. Eventually the live-view of effects and fantastic motion capture will find its way into regular movies. The former of those will be invisible to the viewer, but should result in better direction. The latter will be more subtle than now, like so many other formerly amazing effects.
Revolutionary? No. Just another gimmick that will get played out, with the better points eventually being taken for granted. In the meantime though, James Cameron is going to make more on licensing his new technology than he'll ever make from Box Office. The guy is an expert on that chapter of George Lucas' playbook.