It is. It's easily Shamyanldingdong's worst movie. It's waaaay worse than Lady in the Water. I mean it. It makes Lady in the Water look like Forrest fucking Gump.
The main thing is the writing. The dialogue is awkward-sounding that it makes even the two good actors in this film (Patel and Toub) look bad. The pacing's pretty crappy too. I mean, the movie is an hour and a half. This needed to be around three. So, as a result of the film's meager length, there's a ton of montages, narration and the removal of all side-characters. Even the really important ones like Suki, Jet and all the dudes who were holed up in the air temple. This movie violated the golden rule of storytelling: Show, don't tell. He does a shitload of telling and not nearly enough showing.
The acting really was just another thing to add to the pile. No one really seemed to be trying, except for Patel and especially Shaun Toub. His Iroh is also the only character that even remotely resembles his counterpart from the series. Not so much in appearance, but how he acts. Seychelle Gabriel also did a fine job as Yue. Also, why was Sokka a badass? He didn't become a badass until Book 3. This movie so desperately needed some kind of comedic relief.
Have you ever seen that episode of Family Guy, where Peter goes to see a really boring and depressing play and he just screams "For God's sake, somebody throw a pie!". That's how I felt watching this. It's so gloomy, angsty and depressing. All the fun that was in the series just isn't here.
Shamwow really can't direct an action scene worth a damn either. Whoever was in charge of fight choreography should've been shot. The movements were so long and drawn out and the bending that said movements brought out was usually pretty dinky compared to how elaborate the motions were. In short, a big windup for a tiny punch.
Ideally, this movie should've been handled by someone who had A. directed a martial arts movie before and B. stuck a little closer to the source material (I.E. No white folks. Except Christopher Lloyd as Bumi). The thing about the "racebending" thing though is that I'd have been cool with the cast if they could act, but they really can't.
The saddest thing is that sometimes, you can see how good of a movie this could have been. It could have been the next big movie franchise. Another trilogy to add to the debate. But now, I don't even see how a sequel could work with this movie. There's so little material from which to draw from in this film. Like I said, there's no side-characters, no Ba Sing Se, no nothing.
That's my two cents.