For those of you who are offended by the 'humanistic' and 'naturalistic' content of this film, please get a life. Respect for nature does not equal evil, and if you want to pick, then watch it WITH your children and guide them. That's what parents are supposed to do.
That having been said, The movie's plot IS cookiecutter, the animation was good for a D2V sequel, and the color scheme for the characters was wrong. For example, Balto's eyes changed color between the first film and now. Who knows why?
The original voice cast was almost all unavailable for the sequel, each person being involved in various other projects, which is why most of them didn't come back. As for others, maybe they know that D2V sequels in general are lower quality and didn't want their name associated with it?
Overall, I was pleased, but that's because I tend to read things into movies that they lack, and so I don't find them as lacking. I'm nuts. :)