Having watched it yesterday (for $7 at Rainbow Market Square -- they raised ticket prices!), I have to say it's not one of his better efforts. The Last Airbender is Shyamalan's first foray into action/adventure, and he hasn't quite mastered this genre yet.
To be fair, I didn't find it that bad. Certainly no worse than The Golden Compass, which has a *very* similar feel. But most everybody who left the theatre did express huge disappointment.
The story is about a young boy who returns from a deep freeze after a hundred years to take his place as "the avatar," a master of the four elements whose role is to keep the peace among the four nations (Water Nation, Earth Nation, Air Nation, and Fire Nation). In each nation, there are citizens who have the ability to "bend" their own respective element.
The Fire Nation is the bad guy here. They are technologically advanced, possessed of great machines and metal warships, and they're trying to establish their supremacy over all others.
The world that Shyamalan paints has a strong sense of Buddhist/Nepalese culture, as the avatar belongs to an order of monks that practice katas to discipline their minds and control their psychic abilities. The other nations resemble Mongolian tribes, although Fire Nation is rather like Imperial China with Terra Cotta warriors.
The story is extremely simplistic and the direction is lacking in any kind of inspiration. The ending, however, is quite spectacular, but not enough to make up for the rest of the film.
Speaking of the ending, it is very obviously set up for a sequel, but I fear the sequel will never be made, as the box office will ultimately disappoint. Who will ever bankroll Shyamalan again?