Update by Mike Schramm: Since we took this video at the Art Panel, I've played the Worgen on the floor, and this animation is now fully implemented in the demos here. Going into combat as a Worgen does a quicker animation that sends you into Wolf form (yes, you must be in Wolf form during combat, and it's purely cosmetic). But hitting the transformation ability while a human will give you this animation -- it looks great.
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