Pet Battles is not ready for official testing on Alpha, so we've only had teasers of what's to come.
There are lots of new pet NPCs
in the database and some quests
(daily, account-daily, world/bonus objective, etc.).
There will also be pet tuning
to a few abilities and pets.
Obviously all of this is still a work in progress and largely incomplete. We'll just have to wait for more information when it's ready.