I think they are trying make zoo less frustrating. We have got a bunch more defensive options and the biggest one to come. And while there are some cards that are good in zoo like creeper, egg and chow, they are only good if you use them to control the board, and avoid face all the time. The Leper Gnome/Leeroy zoo variety should be even more terrible.
But that's how you play current Zoo correctly anyway. It's going to get even worse tomorrow, Deathlord for example looks like a great anti-Zoo card until you realize they'll make much better use of it themselves, building a ridiculous army of Jugglers and buffers behind an almost unkillable minion.