Just got back from seeing it. Wow, it was beautifully made, and the story was solid. The colonel's part was a bit over played, but otherwise, the movie was nearly perfect.
The humans and their connection to their technology and machines was paralleled with the Na'vi and their connection to the natural world around them. We see the same thing around us, with people who are attached to their Blackberrys/smart phones/iPhones/GPS nav systems/laptops/HD TV's/PS3's, etc...
Our modern society thinks tech cures everything. The problem is, it also ruins many things along the way, and separates us from the source of everything, the natural world. In the movie, Jake took the higher path.
The short sighted human desire to put profit before everything else might tick some people off, but that's because the mirror doesn't always show a pretty picture.
EDIT: I looked back and see that this post could come across as political. I appologize if it does, but perhaps knowing that many of my views are not related to left or right, but instead, up or down (as in which direction us humans are going).