Scott complains that I rate nearly every movie a "C" -- except Star Trek. That may be true, but five days later, I can't say Avatar left much of an impression on me. It wasn't awful, but wasn't outstanding either.
The uninteresting soldier-infiltrates-the-primitive-natives story reminded me of Dances With Wolves. The heartless corporate militia bad guys seemed too inhumane and one dimensional. District 9 had many similar themes and storyline, but was more convincing and interesting.
The 3D and CGI were interesting gimmicks. But like the last three Star Wars movies, too much CGI just isn't convincing when it is overused. The avatar characters didn't seem real to me and many of the planet scenes seemed like trippy black light posters. Overall, the movie seemed more like a video game.