According to dacardworld.com, the next TCG deck is called Timewalkers: Betrayal of the Guardian. Wowpedia is also listing this as the next release, although detailed information is still missing.
Dacardworld has a release date of February 12, 2013, and mentioned a Floating Spellbook as one of the loot cards. Since the other loot cards are a mount and vanity item, the spellbook is probably the pet loot.
This pet doesn't have a spell or item ID on Wowhead or MMO-Champion yet, but I'm sure after a patch or two, a datamined version will pop up.
As always, we'll have to wait for an official confirmation on both the upcoming deck and pet loot card, but in the meantime we can still speculate and drool over possible pet models. :P
I can only wonder what the Floating Spellbook will look like. Perhaps like the floating, animated books near the Inscription trainers in Dalaran? :D