Basic Idea:
Along with this make carrots appear randomly for the wild rabbits to feast on. The rabbits should be tamable with carrots like wolves/dog & ocelots/cat.

Taming:
You should right-click on the wild rabbit while hold a carrot. Taming should require 1-16 carrots (randomly generated number).

Pet Rabbits:

Once tamed rabbits, rabbits can act/look cute next to you! Adding on to this they should be able to do something useful like cats/creepers & dog/fighting. Rabbits should help you find food by walking in the direction of the nearest potato/whet/carrot plant (a village or wild carrot[seen above]).