The movie had many moments where we feel like we have gone to a known place like Sigourney Weaver, the huge robots, the alien concept. Lot of Camerons trademarks are present in the movie.
The story is more of fantasy than science fiction. Certain scenes reminded me of Harry Potter. Though the story doesnt impress us very much the movie compensates in the visual department. The visuals are spectacular. Never before someone has used the visuals so effectively. Though we can understand how much CGI work must have gone into the final product there was not a single scene where I could actually say that what I was seeing was CGI. This is the main success factor of the movie.
75% of the time we see only strange looking creatures but it doesnt bore us. Yes sometimes I was reminded of the movies King Kong and Jurassic Park as all these three movies has got a lot to do with dense forests.
As the last scene in Titanic there are moments in Avatar as well which will touch our heart.
On the negative many scenes are not believable but it is the story of a super hero in the end who saves Pandora from Aliens. The same audience who would have rooted for the defeat of the Aliens in the movie Aliens will be praying for the Aliens to win this time around. Cameron has successfuly brought out the feeling from us.