This is how i play
Doom longer Targets, Corruption everything, hand of guldan groups, pause (or cast SB), and HoG when Shadowflame ticks are low for double stack debuff. at near full meta, burn the molten core SoulFires, refreash Corrutipn with Demo attack, doom too. Drop meta, unless you need to AoE, then arua burn them like hell!
While in Meta, all dmg is increased by 58% (mastery), all the guides tell you to drop meta at 700 fury, that just seems odd to me ride the damage boost.
Going meta right after getting the doublestack of Shadowflame tickets is nice too, extra damage and fury gen.