I liked it...

The movie, if taken out of context to its origins, is not horrible. It still has poor acting, writing, and directing, but The Last Airbender has some good elements. The problem is that the good elements were taken from the show, and almost everything added by Shyamalan makes it a far worse film.

The movie, if taken in context to its origins, is a failed adaptation of a superior source. It's a bad caricature of an already established universe.

Imagine attempting to purchase a Porsche 911 that you had seen elsewhere, and was advertised as such, and finding it is really a used VW Beetle upon arrival at the dealership. Getting a Beetle would be fine on its own, but it isn't a Porsche 911. If the dealer can't get something that is as good as the real Porsche, why bother bringing you into the dealership?