I'm going to go against the grain here. DD1 was about 18 months old and couldn't have given a stuff about the animals. She was more interested in running around like a maniac and going up and down the escalator in the gift shop.

So complete waste of money for us.

DD2, however, is almost 2 and although we haven't taken her to the zoo yet, I'm sure she'd be fascinated because she has a completely different temperament to DD1.
I think thats what my friend was worried my DD would be like because her son is very hyper he couldn't just stand and look at animals but from what she has been at petting zoos i think she will be fine, or so i hope so!