I liked it better than I thought I would when I saw the previews. My daughters used to watch the first 15 minutes (the parts where he is still little) over and over again. I definitely like the voice they used in the actual film better than the voice in the preview. I also liked that all the talking was in his head (or as a narrator) and he was like a regular horse to the humans, not some twisted Disney version of a talking horse.
I do think they gloss over the whole how he took over for his father part (makes it seem like his father just graciously stepped down, or some horrible accident - not at all related to the healthy growing new stallion
- took him out of the picture - but this is a kids film after all).
There were definitely some parts that made me tear up - I especially liked the part where he's given up hope because he thinks the Indian mare died, and he's loaded onto the train, and he sees his family in the swirling snow.
The animation is reasonably well done, though they have some trouble integrating the computer animation with the drawn animation.
I do, however, love the soundtrack.