Had been a warlock for about 3 or 4 raiding tiers in row, I loved it. My fav spec was Affliction in Cata with Bane of Doom or Agony for dual targets and Haunt on CD, later in Cata I went Demo and liked them both equally...Mastery Snapshotting was fun as hell though.
I love the new Demo...but it isn't on par with Affliction and Affliction is meh more spammy and not as smooth as it used to be imo, good time go back to my DK, loving DW Frost and Blood Dk as OS.