Originally Posted by Hephaustus

For a fire warlock, Conflag SHOULD be a normal part of the rotation since with the right gear and raid buffs/debuffs, it should be at least 2k damage non-crit. Soul Fire is amazingly cheap and while its a long cast, its relatively easy to get off with some sort of haste buff, like Quagmirran's Eye. Even without a haste buff, its worth it to cast sometimes because it scales with your damage better then your other spells. Corruption though, I agree. It has its uses in pve as fire, but not in your normal damage rotation.