Katie doesn't mean to scare the kittens -- she LOVES them. She loves them soooo much that she cannot control her excitement, which she naturally expresses by barking and howling and leaping all over, sending the tiny newcomers flying in terror. Then Katie gets scolded and sent out of the room. Poor, sad Katie!
Himmelman's illustrations are perfect. Katie's face and body language are so expressive.
I also like it because it reminds me of the little dog who lives next door and how she SO BADLY wants to be friends with my cat. She has dug a little trench under the fence to watch him, and when she sees him she'll try to be quiet and motionless (you can see her tail going like a metronome between the fence slats) and he will slowly, slowly approach her and every time he gets close she becomes unable to contain her excitement any longer and starts barking. Then he gets scared and runs away, so she never gets to sniff or lick him like she wants to.
[Edit: Now there is a cartoon of this book! I didn't like it as much as the book -- the reader's voice is kind of annoying to me -- but maybe some of you have kids who would enjoy it. Here's a clip: http://www.youtube.com/watch?feature=player_embedded&v=uvD4fJZJvJM]