BoS will absolutely be the best talent in that tier. I would be my house on it. Blizzard LOVES that ability, and there is a 0.001% chance that they let a PVP talent and a fire and forget talent exceed a talent that requires planning and an understanding of fight mechanics to manage.
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Agreed, but that is something they have never done with frost before. They typically don't give the third tier specs that much attention.