The zoo is nicely laid out and small enough to get around in an afternoon. Our kids particularly liked the play area, the polar bear and the giraffes. The staff were really nice.
It's worth allowing a lot of time up at the back, because the map doesn't really make clear that you can go right around the building, via the vanishing species indoor area (which is excellent). The labelling actually said administrative offices so don't be misled!
I'd agree with other comments that the bears have a pretty sparse and hard habitat, I have to assume that these are being improved soon because other newer areas seemed quite appropriate.
The "beastro" cafe has a pretty good fast food/wraps selection, including healthy grilled chicken sandwiches and BLTs.
One downside was not being able to work out where the actual entrance was (GPS misleading me). It'\s on the Parkside Avenue side. There is a decent size car park so until you've seen that, you're just looking at back gates and walls.
All in all a great time. There's even enough under cover stuff to go on a rainy day.