EDIT: Dangit, can a mod move this to recent updates and snapshots? I messed up.
Disclaimer or whatever you wanna call it: I have not seen any topics on this. I searched it, too. So if there is one, forgive me.
Many of you may not know, but Dr. Zhark and the Mojangstas added something hidden in the new snapshot. Zombie and Skeleton Horses!
What do you think of them? Could this mean Zombie Jockeys? Or a Skeleton Jockey? (Not to be confused with Spider Jockey)
They can also be seen in this video, by GameChap:
As you can see, they don't do much yet. They don't even burn. What will Mojang do with this undead creatures? I guess we'll have to wait and see!