I saw this last night. It is an excellent movie. I highly recommend it; especially if you are an avid Sci-Fi buff.
I did notice that this movie resembled "Dances With Wolves" quite a bit. The Story line is great and the special effects are superb. The acting is actually quite well too. James Cameron did not disappoint; hopefully he can make up for all the money he spent on this movie.
When I saw the various ships and the organizational structure of the background story, I realized that it was quite similar to the story I am writing. But since this storyline based more on the Scientists; or more specifically, the wounded Marine who joins a Science experiment, I realized it has a different plot line than what I am shooting for.
Great flick, either way.