Mooshroom

Mooshrooms are a mob that Notch and Jeb_ have mentioned on their twitter accounts. It is unknown if Mooshrooms will be added to the game. If they are added, then they will probably appear in the up and coming 'Mushroom biome' mentioned by Notch. Mooshrooms are believed to be added in Beta 1.9.

Trivia

 * The Mooshroom's name is a portmanteau of "moo," the sound Cows make, and "mushroom."
 * Mooshrooms will have the ability to be 'sheared'. You will probably get at least one red mushroom when doing so.
 * In the picture Notch released, the Mooshroom appears to have red Mushrooms on its head and back. These will most likely be able to be sheared off of the mob if they are added.
 * The picture also shows what seems to be a new type of dull gray grass block, likely the mycelia of the large mushrooms.