Avatar by both definitions is applicable. The story touches on both reincarnation (the sanskrit definition) as in the continuation of life energy (think Gia here) , along with the obvious modern day definition where it is something representing us that isnt' really us.
The storyline was basically Pocahontas but sci-fi (aliens, Gia, etc.). The Pocahontas equivalent was a strong female character, the likes of which I wished were available in the movies of my childhood, always craving for the strong competent independent female. The storyline wasn't big enough for me but I will still be going to view this movie on IMAX this Sunday. Yes, it was that good in my opinion.
The CG is awesome, the motion capture some of the best to hit the big screen, the acting sold, the characters well presented, the Pandora landscapes breathtaking and the story sufficient. There were a few "cheesy" parts, but nothing I couldn't overlook as a whole. If you like sci-fi and CG art, this is the film to see this holiday.