Essentially you are placed in the world of Avatar as a marine, sounds inviting but the game robs you quite a bit.
Many of the hints to give you help in the game, also do not await for you to read all of them, as they will simply vanish after a certain timed amount of time, thus leaving the player with very little clue on how to get to the desired location or gather what needs to be gathered. As well as the start menu holding much of the controls and the information on different weapons should be easy to navigate through, but is quite hard to find your way making it all the more difficult to find what you are searching for. Simply causing frustration and forcing many players to give up and simply experiement until they figure it out.
Graphics are also a factor in the game, the first thing you will notice is ships and humans seem to look, average by today's graphic's standards, but the lip synch leaves much to be desired as lip movements are not even close to the audio being said. One may go as far as to believe that the game was dubbed into English from another language, due to the odd lip scynching that you are first introduced to. The environment that you are placed in however does look rather lush and well made, this is quickly forgotten about because during combat, the game is unable to sustain itself and it quickly begins to lag during a fight.
What one must also note is the control scheme coupelled with the medicore camera angelling the control scheme is not user friendly. The controls are quite unique to only this game, very few are shared between games which can cause great confusion to the player, and will result in the player having to cycle through different combinations to figure out what is best suited to their situation, however that can easily have already led to death, thus meaning they must restart at the last checkpoint, which are not marked for the player, so they have no idea how far back they are going. Though it should be noted most of the time, they are not sent far back into the game.
As for story, the choice given to you on who to play as is quite obvious, but unless you have watched the movie first, the choice to fight for the Navi does not seem to be very convincing as you very likely expect that being in the military means killing your enemies. As such, the player is not given to much of a choice unless they are more curious on how to explore the Navi, but the change does mean there are new rules to combat, rules that you will have to quickly master after already spending so much time struggelling with the controls for the Marines to begin with. More over the difficult controls must be mastered extremely quickly because fighting marines is more difficult than taking on viper wolves, and because as a Navi you must close ground with your enemy that only makes it all the more frustratiing.
Overall the game creates much frustration for the player, and the story does not capture you to start, which also takes away from it's replay value. The game does not do the movie justice, and is definatly not on par with the masterpiece that James Cameron created.