The only problem is that Cameron doesn't seem to know that he's doing this. The stock characters and the plot pilfered straight from Dances With Wolves would be forgivable if Cameron viewed them as regrettable elements that are necessary to build his overwhelming audio/visual universe. Instead, he seems to take the white guilt narrative and heavy-handed politico-historical allegory seriously. And so the movie spends lots and lots of time on the kind of tooth-grindingly patronizing business (a white man discovering that the 'primitive' race is noble and pure, but not quite smart enough to defend themselves without the leadership of a White Messiah) that would give Kevin Costner and Steven Seagal mindboners. It's a painfully earnest and obvious scenario played out by hand-me-down characters from other, better James Cameron films.
But just when you're ready to hunt down James Cameron and kick him in his well-intentioned but privilege-addled nuts...a giant rhinoceros-looking thing charges through a richly detailed jungle and right into your grill, a giant mecha-mercenary crashes through a river and the air in front of you fills with mist, pterodactylesque creatures plunges through the sky and you get a momentary headrush of vertigo. In those moments, Avatar isn't just another muddle-headed exercise in empty spectacle. It's an experience and one unlike anything you've ever had in a movie theater before. It's a full-sense emergence in an exquisitely detailed, fully realized 360 degree alien landscape. And then it's Dancing with Space Smurfs again.
The contrast between the lukewarm cliches of the narrative and the full-tilt techno-gasm of the imagery may cause brain leakage, but it's a byproduct of the protean nature of Cameron's unwitting paradigm shift. Avatar is an intermediate species, like one of those prehistoric fish with wrist bones. In the future, this sort of technology will go towards making hour-long non-narrative films that immerse the audience in exotic and intense environments without bothering with the drudgery and distraction of plot and characters. They'll probably have their own theater, right next to the Food-Pill dispensary and the jet pack repair shop. For now, we must endure the outdated demands of conventional cinematic structure if we want our revolutionary technological innovations.
Of course, whether it's a good idea to turn a movie into a rollercoaster is a whole other question. It might be wise to remember that there's probably a reason that the Iron Wolf only lasts two minutes.