While the visuals are undeniably beautiful and the battles are exciting and intense, this movie is also more style than substance, consisting of a predictable plot, flimsy two-dimensional characters, and a story that drags on longer than it should.
The Na'Vi are kind, gentle, noble, and just unrealistically "pure" and "good". On the other hand, almost every last human is portrayed as greedy, ruthless, and cruel.
There are no shocking twists. The main character is an idiot. (Soon after being warned that Pandora is extremely dangerous, he starts running around touching random objects!)
Don't get me wrong; the graphics are definitely worth checking out, but one will find much more eye candy than brain food.