Post by Pixels
I just made a quick affliction spec that would be a lot more advised:http://www.wowhead.com/?talent=IqMrbRfkqtfooZxx0tM
It has raid benefiting talents: Malediction and 1 Imp Health Stone, as most locks will not have this it can allow more then one Health Stone per person.
I took points out of Suppression because it isn't needed, try to hit 202 rating with gear so as to benefit immolate and shadow bolt (which you will cast as affliction).
I put points in Destructive Reach, the increased distance is nice but the reduced threat is what makes it worth the points. I also put points in Imp Drain Soul for the same reason, the mana bonus is nifty for grinding/farming also.
I put a point in Dark Pact because in a lot of raids you will take damage and life tap may not be as suitable, Dark Pact will be all you need just as long as you get a pally to buff it with wisdom. Druid, Mage and Kings would also help for the Imps Regen.
I took points out of Aftermath, it is useless - it is a movement slowing debuff that has little place unless you are lucky. I put these points into Devastation which will help with Imp Shadow Bolt up-time.
If you need any other advice about playing Affliction, just let me know. Keep in mind this spec was built assuming you are PvE raiding, hope it helps.