Most of the buzz I've heard about this movie has been about the special effects. And, to be sure, they are the best I've ever experienced (especially in IMAX 3D). The CGI is so well woven into the film, that you very easily forget Pandora and the Navi don't exist anywhere but in software. However, had the story not been so engrossing and the acting so effective (particularly by Zoe Saldana), I don't think this film would have been as engrossing as it is.