Eww...

Chocobos? Definitely.

But other stuff? I really hope not. Not another ridiculous mount system ala WoW with a billion species out the wazoo, it'd kill all feeling of chocobo being special. I mean, sure, maybe the odd one that fit into theme somehow, but I can't think of any... and I'd hate it if they added something like wargs -.-

If anything what'd be most amazing is more active emphasis on chocobo with a breeding and colour system.