Let me first say - I liked this movie. I liked the theme of respect and kindness, of friendship and honoring special bonds. I liked the portrayal of dogs (except the whole "master" bit), I think they captured so much of what attracts us bipeds to those furry quadrupeds.
But, and you knew it was coming, I couldn't help but cringe when I saw the horde of dogs managed by the "bad guy". While the "hero dog" is a goofy, eager-to-please, golden-hued retriever, every single menacing dog is black, dark, muscular. They are Rottweilers, Dobermans, Pit Bulls, Mastiffs and one English Bulldog and they are not portrayed nicely. I mean, they *kill* people, even if it is only b/c their "master" told them to. That is just not how types of dogs should be portrayed.
Even when the ending comes about and you see the dogs are nothing more than a reflection of their owner/guardian, that they aren't inherently bad, I couldn't help but feel a bit slighted.

So it is difficult for me to watch Up and not feel as if the creators have bought into the hype, that they are perpetuating stereotypes and myths that have caused the deaths of thousands of dogs.
This film would have been a lot more fun, a lot more enjoyable had the dogs been a mixed bag, had they been different colors, different sizes, different breeds (mixed breeds too) and had the "good" dog not been the stereotypical "good" dog with his blond hair and retriever'ish looks.