I saw Avatar for the first time last night. I went in expecting to enjoy it, and I did. I am a big James Cameron fan, so I pretty much knew I would like it, but I didn't know how much I would like it. I REALLY liked it.
So, after seeing the movie, I came home and looked up what critics were saying. For the most part, professional film critics like it. Film students and internet film buffs seem to despise it, wishing it to fail just because.
The biggest complaint I have read? The story is unoriginal. Newsflash for the uneducated, young, and ignorant people: NOTHING UNDER THE SUN IS NEW. Yes, Avatar has a plot that is similar to Dances With Wolves and at least a dozen other movies. There are no new plots out there, people. Read some books and you will find that everybody reuses the same plots. Why? Because there are only so many stories to tell.
Do yourself a favor and read a half dozen Shakespeare plays. Now you know the plots to 90% of movies ever made. The Taming Of The Shrew? Othello? Romeo and Juliet? Even movies that are not direct copies of the plot use large chunks of it. Why? Because Shakespeare himself didn't invent these issues and plots. They are stories from when men started to tell stories, passed on down the time line.
Common plot themes that tons of movies use:
Industrialized, "civilized" men attempt to bring "civilization" to the "backwards" indigenous people. They may be the good guys, but usually are portrayed as the aggressors who are exploiting the natives and destroying the environment. (Avatar, Dances With Wolves, Fern Gully)
Man and woman marry/fall in love/have a child/become friends... Man or woman is from a race/species/sex/family that others in society do not approve of. Strife follows. (Othello, Enemy Mine, Romeo and Juliet)
And the list goes on.
A plot cannot be original. The way you tell the story can, and I think Cameron did an excellent job with Avatar.