The word on the street is that creepers don't like ocelots/cats. While they now are better at chasing you, they won't go near a feline. So people will need a cat and dog for defensive and offensive purposes now.
And the villagers can open and shut doors, though there might be a bug with some doors. Hopefully this means that Obsi won't have to fence in the villagers any more so they don't leave their villages.