Only played this a little while, but damn it's cute!
Reminds me of kinectimals, and nintendogs on my 3DS.
But with a lot more variety...and probably more stuff to do.
Started with the big cats (can't think why :P ) and now have a little cub in the exhibit too. Hehe, too damn cute.
Graphics are cute too, and the animals move quite well and realistically. They behave as you'd expect, when stroking and brushing, and even have a little fun without you pestering them all the time.
Just give em a toy, and watch em go...or sit back and let them make their own fun.
I especially like the thought bubbles...makes it easier to do stuff with them, without having to search for ages in your bag to find what they wanted.