patch 5.1 extends the "defeat the pet tamers" questline with a new quest, pandaren spirit tamer. you are required to defeat four new tamers, each an elemental spirit with three legendary-quality pets. the pets were mostly elemental (each tamer had a miniature version of itself), critter, and dragonkin, with some variations. you get the quest from the pet battle trainer in either the horde or alliance pandaria capital, and the tamers themselves are located in the vale (earth), jade forest (air), dread wastes (water), and townlong steppes (fire).
i started off with stoppable force (darkmoon tonk), francois (darkmoon monkey), and wild eyes ramona (softshell snapling). stoppable force was configured for dragonslayer mode, with charge selected for its first spell slot. the thundering (ie earth) tamer is reported to cause a lot of people trouble, but i got it down on the first try. the air tamer gave me more trouble, because its elemental pet had two flying attacks which chopped up my turtle something fierce. so i switched her out for frederick the oily slimeling, configured him to use creeping ooze for elemental wastage, and rocked it out. then i proceeded to one-shot the two remaining tamers.
now, to be honest, when i say i "one-shot" them, what i reall mean is this. i start a fight and see what pets it has. then i run away. i adjust my pet team composition, and start another fight. when i see that its lead-off pet isn't the one my lead-off pet is strong against, i run away. repeat until i get the match-up i want. then i one-shot the fight.
after defeating the fourth tamer, i hearthed home and turned in the quest back where i started. the trainer gave me a choice of four pets, each a mini version of the spirits i had just defeated. being a destro warlock, ellspeth of course picked the fire one. cute little rascal, ain't he?
once you've completed the quest, your allowed to go back later and each tamer will have a daily quest for you to defeat them. the reward bag has a chance to contain another mini-spirit, so collecting all four is doable. unfortunately right now the dailies are buggy, and aren't showing up for a lot of people. hopefully this will be fixed before long.