I grew up in Pittsburgh and moved away, so I remember this place from my childhood so it was neat to come back later with my own child. They've obviously improved over the years, and in the last two years really added some great aquarium set ups including penguins (there's even an NHL hockey banner in the tank with them!) and a shark tank you can walk under. We really enjoy this zoo, as you can walk among the animals and get close to deer and kangaroo.
As another person pointed out, the food completely sucks here. Terrible, greasy, and god awfully pricey. Pack a lunch!