I have never heard of raccoons being a threat to dogs or cats, but I could definitely see danger in unguarded kittens.
For the most part raccoons are scared of dogs, and humans, until they learn they can steal a lot of good snacks from campers or trash cans. They really don't even look all that threatening. Most people who don't keep poultry don't even regard them as predators, but rather a nuisance that will knock over your trash cans looking for food.
I know I was surprised to hear how vicious they could be if they get their little paws on a chicken. Their little feet are so cute and they even wash their food before eating it. I think they're just kinda cute fat trash pandas.