Assuming the sims I ran on my warlock (645 ilvl, link in sig) are correct my stat weights are currently:
GoSup/DemServ: Int > SP > Crit > Mult > Haste > Vers > Mastery || 19,480DPS
GoSac/Cataclysm: Int > SP > Crit > Mult > Mastery > Haste ~= Vers || 17,871DPS
Keep in mind this is still casting Rain of Fire in my single target rotation (on that sim) - working on fixing that. Funny to see mastery fall so low tbh.
edit:
Simcraft with updated (thank you Ghaddo)
These are what I get for my warlock.
Destro GoSup/DemServ:
http://i.imgur.com/wriif9h.png
Destro GoSac/Cataclysm:
http://i.imgur.com/yPmE7EF.png
Destro GoSac/CharRemain:
http://i.imgur.com/fIgY2G9.png
Destro GoSup/CharRemain:
http://i.imgur.com/GpAWEGy.png