So knowing James has two of the highest grossing movies in the world I'm beggening to sense their has to be some pressure to make this coming saga a hit. In my opinion like other fairly successful sagas such as Underworld, I'm thinking they should follow in that direction as for the format and outline of the series of 4 movies. I think Avatar 2, should be a direct follow up sequel . As for the plot of part 3, I believe in order keep the viewers attention should go back and make 3 a prequel to the original. That will build suspense from the ending of part 2, and also shed light on Sullys brother as a scientist on earth as to why he wanted to go to Pandora so bad. It will also give another chance to see some of the main actors faces in the flesh and the suspense of how and why they really killed his twin... Possibly a conspiracy rather the paper in his wallet. This type prequel plot for avatar 3 could build up anticipation for viewers to see the very ending in part 4 taking place on Pandora. It's just a valid suggestion having found out that they were making three more avatar movies. That's a tough one knowing how great the first did, quite a bit to measure up to. God Bless and good-luck!