I quite enjoyed the movie, I don't think the story was terrible, just very simplistic and traditional. That being said some of the dialogue (primarly the obvious Iraq war references) is rather cringeworthy and I would have liked the villians to have had more defined, deeper motives. But oh well, that's not one of Cameron's strong suits. What he is strong at is entertainment and getting you caught in the tension of the moment.
The visuals are fantastic, but I think people need to know that Pandora is not as original as they think.
Of course I of all people am gonna notice when a movie looks like one big Yes album cover. So much of this movie's visuals are lifted straight from the work of Roger Dean.
His work featured a lot of the things Avatar has, floating moutains, twisting arches, psychedelically colored dragons and bonsai-esque trees.
And I think it goes waaaaay beyond coincidence.
These aren't copyrighted ideas, but jeez Cameron, would it have hurt ya to give this guy a little credit?