Avatar=Dances With Wolves+The Abyss*10+Starship Troopers/10+Gorillas in the Mist
Dances with Wolves for its obvious plot similarities, The Abyss for its spectacular visual otherworldness, Starship Troopers for the obvious plot similarities, and Gorillas in the Mist for the anthropological side story (and, of course, for Sigourney Weaver)
I really liked Avatar, but it didn't live up to the hype. There's probably no way that it could have. I thought that it was visually spectacular, but it spent too much time dwelling on the (spectacular) Pandora visuals, and too little time on character and relationship development. I didn't necessarily believe the relationship between the leads. The Norm/Jake dynamic went back and forth without any explanation. Plus, maybe the "performance capture" technology would've been cooler if the performances themselves (Sam Worthington, in particular) were better?