I just came back from seeing this movie and this is really the best use of CGI ever! Without a doubt!
Now, the story, as has been pointed out, is not groundbreaking or original at all. But it's told in a very good way. I definitely got a cowboys vs. indians, Pocahontas vibe from the story but I don't think it subtracts that much from the film.
The attention to detail Cameron did to Pandora is second to none! This is not CGI for the sake of CGI, James Cameron literally created a whole world! The flora, the fauna, the atmosphere, the day and night cycles, goddamn was I blown away by the attention to detail and scope of the enviroment!!
SPOILER ALERT!!
The part I loved the most about the movie was that the didn't take the cheap way out when Jake was fighting Quaritch! When Jake rams the knife into the cockpit and he takes off the... well the cockpit glass because I can't remember what's that called, I was so expecting him to die from the plot device about the atmosphere being deadly, thank you for not doing that James Cameron.