And here lies the final chapter in the Taming of the Worgen saga: Mania reports that, just a little while after the troublesome Worgen Garwal was hotfixed to be untameable, Blizzard has magically changed all of the already-tamed Worgen to level 68 (or Hunter's level minus five) wolves. Why level 68? Because, Mania says, they've all been turned into Winterskorn Worgs, a level 63-69 NPC that wanders around the Howling Fah-jord.
So that's the end of that. Obviously, no one really expected to keep those pets as their own, and especially with all of the Worgen-as-playable-race speculation flying around, it wouldn't do for Hunters to have one of those humanoids at their beck and call. Some Hunters who went to the trouble of taming probably won't be too happy. But the good news is that the new white wolf in your stable is completely fixed -- it has all of the normal talent trees and abilities that wolves are supposed to have. Guess you and your pet Garwal were just never meant to be.