It was a great pseudo-open world game with nice graphics. You don't see this kind of ambition anymore in a game heavily based on a movie. My only complain was the mixed human-na'vi campaign at the end of the RDA campaign, it was really stupid and out of place.
The Symbian^3 (Nokia HD), Android and iOS game by Gameloft Barcelona was also really cool. It was a weird mix of completely linear game with a big open-world level at the middle of the story, for some reason. So far, the best Spanish mobile game ever developed. It took me like 30 retries to finish the Symbian^3 version, since it had some kind of memory leak that crashed the game every ~30 minutes, and I was playing with the Nokia C7-00, the most powerful Symbian^3 phone (along with the N8).
Wii/Playstation Portable game was also good. Linear action game with some stealth mechanics. Motion controls were tedious on Wii, but not a big deal.
The worst version is probably the DS game, a very boring Phantom Hourglass clone, and the Java game, one of the most uninspired Gameloft games ever (developed by Gameloft China, iirc).