this is a nice, fun, great plugin that works with 1.8 and the admins could have fun with it ^_^ http://forums.bukkit.org/threads/fun-rpg-mobdisguise-v1-62-transform-into-any-mob-and-players-too-no-client-mods-1185.28750/
As this is a cool plugin, Max doesn't like adding plugins that aren't needed. I can also see many problems with this, combined with /sneak, you could run around as a creeper and when people would try to kill you, you wouldn't die, which in turn, would cause Admins and Mods to be spammed with /tells and the forum would explode with everyone saying, "I can't kill certain Mobs."
Although I would love to have access to this plugin, maybe not give normal players the ability to use it. I personally would be just as content with having Max or Blat approach me as a creeper as I would having the ability to do that myself. I think this should be a go