I really like it. It has a bat enclosure you can actually walk through, a great nocturnal section and a really good penguin/seal 'coast' where you can actually go below ground level and watch then little guys swimming around. It's also got a pretty good bug house and reptile enclosure.
I think it is better than London Zoo but not as good as the Lake District Animal Park (the only others I have been to). I think it's pretty expensive though, would be a lot of money for a whole family. And yes it has got a strong emphasis on kids, but I guess most Zoo's do really. Certainly wouldn't stop me going (well maybe during the holidays it would!)
In fact I might go again with the GF on Monday if the weather is nice!