For those who don't want to read this all, some bullet points. Read the entire piece for in-depth description and analysis, but these bullet points are the main, stark differences between Project 880 and Avatar:
- Earth and its environmental problems are explored
- We see Josh Sully's Avatar being born
- It's revealed the Avatar program exists to train Na'vi to be an indigenous workforce for the Corporation, since it's so expensive to send human workers
- There are more humans, including a bioethics officer on the take, a video journalist, a head of the Avatar program and a second military dickwad
- There is an Avatar controller who is burnt out because his Avatar died with him in it. He committed Avatar suicide because he had fallen in love with a Na'vi girl who had been killed by the military
- The Avatars have a Na'vi guide named N'Deh, who is sleeping with Grace
- Grace survives the soul transfer
- Josh Sully gains the Na'vi trust by being a member of the community. He also excels in a major hunt
- Josh Sully shows his leadership not by taming a dragon but by leading a raid on Hell's Gate to rescue prisoners
- Josh Sully isn't the only Na'vi to ride a big dragon
- Pandora is a living entity and it sees the humans as a virus; it has been mobilizing the plants and animals to attack all along because it wanted to force the humans out
- There is no unobtainium beneath Hometree. The military just wants to wipe out the local Na'vi to send a message to all the tribes that they must be obeyed.
- Some of the humans and the Avatar controllers rise up in the final big battle
- Josh Sully tells the Earth that Pandora will give any humans that return a disease that will wipe out humanity