Now, anytime I go with the family to the zoo, I leave all my telephoto at home, and bring a wide prime, because shots of my kids looking at the animals is all I'll be interested in looking at later.[/quote]
I read your comment and I agree that zoo photography can definitely get more interesting if you combined it with street photography and an emphasis on candid portrait photography. The more interesting pictures that will come from a zoo will not be a close up of a tiger or bear, that's been done a billion times, but rather the shots of people's reactions, expressions, and interactions with the animals. IMO.
Candid portraits are great at a zoo because people aren't paying attention to the photographer, one of the few environments where you can shoot candid portraits with ease.