Loves in the Air ~ Big Love Rocket that doesn't exist I swear / Pink tallstrider
Noblegarden ~ Grey tallstrider
Brewfest ~ Brewfest Ram / Brewfest Kodo
Hallows ~ HHM Horse
(may have missed one)
Ideas for others that i have:
Lunar Festival ~ Moon rocket, when mounted a trail of Moonlight emits from the rocket (instead of flames, its white moonlight, Lunar powered!). There is even a glittering moon sticker on the right side of the rocket.
Children's Week ~ Tricycle. seriously a tricycle that you ride around. Land mount, and obviously with lots of tassels

Red version for horde, blue for alliance. Maybe attainable after completing the new-daily Orphan fight to the death, kind of like the wow-Hunger games. All orphans are equal in stats, so its all about strategy and ability.
You can only queue for it once a day, but whomever wins the deathmatch of 12 gets a trike

Thanksgiving Festival ~ (duh, flying turkey mount)

Christmahaunakwanzakah ~ An actual flying Reindeer mount (no hops needed) as Wain mentioned in a different thread. That would be neat.
What do you guys think? What types of mounts out there could be implemented in furture holidays?