Surprisingly good commentary from Wowinsider:
http://www.wow.com/2009/10/08/patch-3-3-ptr-warlock-pets-bite-back
Article from last week AznDave and I have discussed, and will be appropriate until 3.3:
http://www.wow.com/2009/10/05/blood-pact-the-hidden-power-of-demonology
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I raided as Affliction and farmed as Demonology in Burning Crusade. (Truth be told, I also raided and PVPed as Demonology quite often and was still competitive.) I like the former as it's not just spamming the same spells and requires a little more juggling. Demonology is, IMO, what separates Warlocks from Shadow Priests and Mages. It just has not been as viable in 10 man raids.
I'll be going back to Affliction as my primary spec. Unsure about secondary. I raid as Destruction now, but it is kind of boring.