At the moment, the theorycrafting seems to lean towards 0/13/58 or if Molten Core procs from Curse of Agony then something like 7/1*/4* but as it is the other problem I can see with heavy destruction specs is that owing to the rating requirements at 80 then people might not be able to stack enough hit/crit to make them worthwhile (even with 5% coming from talents) initially so we end up with the situation we had in The Burning Crusade (at least to start with) - Affliction had the lightest gear requirements and so ended up as the de rigeur DPS spec.
WoTLK Speculative Talent Builds - Part Deux - The Warlocks Den Forums