I find the movie worth waching in 3D. It is a good movie, not an extraordinary one. Plot is nice but over fantacized like cartoon for kids. Same plot could have been more realistic. I think it is over expensed movie. 

As for James Cameron  Judgement day and Titanic was far more better than this one. Anyway I am not much a  fan of SiFi movies.

@Jareko paat. In a public radio interview James told that the Navi characters were influenced by some of the tribes in Africa and Amazon. May be that is the reason behind the African accent.