Short Story: Don't use it. It lowers your DPS.
Take a look at http://code.google.com/p/simulationcraf ... leOutputT8
Scroll down to Warlock_T8_03_13_55 look at the Damage Per Execute time of the various spells:
CoD: 12,356 dmg per cast
Immolate: 10,485 DpC
Conflag: 9,263 DpC
Incinerate: 6,610 DpC
CoA: 4,662 DpC
So, we take those numbers and set CoA as the baseline we get:
Incinerate: +1,948 DpC
Conflag: +4,601 DpC
Immo: +5,823 DpC
Now some of you might be saying, but wait Elven CoA is a 1.5s GCD and Incin is a 2s cast (talented) so CoA is better.
CoA: 4662/1.5 = 3108 DpS/C
Incin: 6610/2 = 3305 DpS/C
Incin > CoA by 197 DpS/C
What does this mean?
It means for the GCD you're spending casting CoA you could be doing 2-6k more damage.
Conclusion: CoA lowers your DPS.
PS - Ginxx is a noob.