They've done a great job of putting a lot of animals into a walkably small space without it seeming crowded at all. The kids liked having the log ride etc. We were all especially impressed to see an echidna in the Australia section. The sea lion show was terrific.
We got here with our 5 and 7 year olds at 10am. We'd seen it all by 3pm.
The zoo website has a section for lodging that will lead you to some great hotel deals.