It's Brewfest in the world of WoW, which means Coren is just standing around, waiting to duke it out over beer.
I have been taking four characters every day to Coren and have had four mounts show up in the Keg shaped container.
Unfortunately, two were rams on one character and two were kodo on another.
I have also seen the Shanker FIVE TIMES (between two characters). But never on the rogue that can actually use it.