What's the best PvP Spec for Warlocks?

I use 18/0/43 Nice for raids and pvp. Don't forget those times I get 2 instant shadowsbolts.

lol.
23/38/0 2v2, 3v3
5/45/11 3v3, 5v5
either works well for BGs.

How come your Demo tree has 45?

Isn't it 9/41/11 ?

I usually go:
http://www.worldofwarcraft.com/info/classes/warlock/talents.html?0500000000000000000002050030133250102531351505000010000000000000

Felguards go oom so fast without mana feed.

You could take points out of demonic tactics to put into imp. Life tap and possibly Soul siphon I guess.  Maybe i'll try that... I haven't deviated from SL/SL for months though so probably not going to happen.

27/34/0
There is a lot of variations from sl/sl, but this is the spec i like most.

I use this variation for sl/sl at the moment. Seems to work fairly well for the most part.