This is a terrific movie. It's hard to explain exactly why, except that the complete package of animation, 3D, and artistic design are just captivating. The 3D animated world is beautiful and enchanting, the action is realistic, and the acting is good enough for this genre.
The negatives: the plot is a bit predictable, and why does the savior have to be an earthling, and a white guy at that? As if the indigenous people are incapable of coming forth and doing it themselves.
All in all, though, I would not hesitate to recommend it. It is a wonderful experience, even at 2 hours, 40 minutes.
I am a fan of both Johnny Depp and Marion Cotillard, but I was a bit disappointed in the movie. The chemistry between the two actors was not great, and the pacing of the movie was a bit off.
I agree with one of the other reviewers that the characters were not developed well enough. It would have been nice to get more background on Dillinger and Frechette.