I'm not sure that I can add anything original to the thousands (hundreds of thousands?) of words that have been written about "Avatar." Visually, it is a feast for the eyes; a magnificent accomplishment by James Cameron. But the story is nothing that you haven't seen before, especially if you've seen "Dances With Wolves."
Cameron's dialogue isn't as clunky as George Lucas', but he'd be better off leaving the writing to others. The performances are OK - Sam Worthington is all right in the Michael Biehn role, but Biehn was better in "Terminator" and "Aliens." Sigourney Weaver is fine in the Sigourney Weaver role. Paul Reiser did a better job in the evil corporate weenie role than Giovanni Ribisi. But Cameron has a real problem with villains, they always seem to come across as one-dimensional - at least, that is, when they're humans. In fact, they come across a lot like the guy to the left. Which is too bad, because I really like Stephen Lang. But here, he's straight out of a comic book.
But even with those drawbacks, it is an interesting story, and it's hard not to get excited in the final act - predictable though it may be. It's well worth seeing on the big screen.