I suppose the rationale that dogs do "take after their owners" is true to some extent. But one can't make a broad sweeping judgement against a certain breed of dog, like your basic Pit Bull, for example. These dogs can be some of the friendliest and most gentle dogs out there, but all it takes is some stupid crack monkey breeding 'em in his filthy back yard for little else than fighting stock to demonize the entire breed. I don't think the idiot media helps either.
Personally, I have English Springer Spaniels. Great companions, good around kids, loyal and very intelligent. All of the things humans seem to be lacking in general.