We got our Council kill last night, I was progressing most of the night as affliction but I ended up going destruction in the end, while it was less overall damage, it was more damage on the right mobs when they needed it. Since I only had a few pulls with destro, I definitely have room for improvement, but at least I ended up on rank#14 with 183k dps.
My advice would be to go Mannoroth's Fury to get as many targets in your RoF as possible. Channel as much Chaos Bolts as possible into priority targets, but save an ember so you can Shadowburn adds before they die. When bosses start going below 20% start pooling embers for Havoc and use it on 3x Shadowburns.
Here's our kill from my POV, a bit low quality but you should see what's going on: http://www.twitch.tv/khadjid/c/2175660