Avatar is a wonder to look at. James Cameron's film is a technical marvel, and the world he creates is beyond realistic. The only shortcoming with this film is character development. The characters are all one-dimensional, and while our hero (Jake Sully) has a change of heart about the alien tribe and the human's treatment of them, the portrayal onscreen is not fully fleshed out. The bad guys are just bad guys, with no complexity to their characters. Richer characters would make this an instant classic.
This movie is enjoyable and has moments of outright laughter. The performances are solid all around, though Steve Martin is under used. Meryl Streep is very good and consistent throughout. The script is somewhat predictable, but is overall solid. What is missing is that touch of greatness. I would rate this a B to B+ movie. It is a good film and makes a good date night movie. The themes are a bit mature for a younger crowd, and not good for children, who will find this dull.