Pet Battles

Overview
Pet battles are a whole new system for WoW. Yes, they are very similar to Pokemon battles. You start by using one of you companion pets. Wild critters that you can start a battle with, are displayed on your mini map as a green paw. When you are in visual range of the animal, you will see a green paw over it's head.

There is also a quest chain you can pick up that leads you to NPC trainers. Trainers that you can battle will show a thought bubble on your mini map.

Pets
Your companion pets are in different type categories: elemental, critter, beast, flying, dragonkin, mechanical, humanoid, aquatic and undead. Each pet has 3 attacks that it can use that are each of a different type. Some moves are stronger against different types, and some are weaker. It will show a red arrow pointing down if it is weak against your opponent, and a green arrow pointing up if it is stronger. You can view all of the information about a pet in the pet tab of the mounts & companions screen. (SHIFT + P)

From this screen you can view a pets information, change out your pets, heal your pets (15 min cd) or you can even crate the pets you have captured. Why?  You can sell or trade the ones you have captured. You can also q for a pet battle. I qd for one and the person I was against left before it was done. lol But it is a turn based system and you do not see your opponents name.