17/44/0 - imp Fear/Felguard/Bane
Description:
Very similar to the previous build with the exception of dropping points from imp LT, amp curse, and grim reach and putting them into 5/5 Bane. If you have a team that can hold the DPS target still (like a rogue or mage) you stand to gain a lot in the area of dps and burstability on a target.

Strengths:
Very high survivability via Soul Link and Master Demonologist. Dps remains high if you are focused hard. Your pet is also very difficult to kill and peel off of a target (thanks to Demonic Empowerment). Higher sustained and burst damage on your target via SB spam.

Weaknesses:
Less regen than the other FG build since you don't have imp LT. Your dps (not your pet) is also heavily dependent on both casting spells and LOS so it will take a substantial hit from pillar humping.

Note to moderators: I posted this in the PVP section rather than the Wrath of the Lich King section since there are not talents that will be unique to the expansion. This will be released prior to the expansion and I was hoping to get some discussion about builds that are balanced specifically around level 70 arena pvp with the new talents. If you feel it belongs somewhere else feel free to move it, though.
What, no love for the destruction tree?
I mean I like your builds and everything, and I think they are wonderful for those who want that same playstyle (I have always loved the idea of improved fear). I however currently use destro when doing PvP, so I will be using one of the two following builds.

Fire Destro + Soul Link 0/11/50
Lets face it, any warlock who wants to do PvP will abuse the fact that SL has been moved down the demo tree. The build is designed to deliver nasty burst DPS through the implementation of Backdraft, Fire and Brimstone, Backlash and if you are lucky, Molten Core. Sure it may take some luck for all the stuff to click into place when you need it, but when it does your damage will go through the roof.
Main thing that is wrong with this build is survivability. You have SL, but you are missing the common survival talents for destro, Soul Leech and Nether Protection.

Chaos Bolt+MC 5/0/56
The main purpose of this build is to play around with Chaos Bolt, to see how useful it really is in PvP. It is similar to the above build, however I have added improved corruption to give a higher chance of Molten Core procing, and added Soul Leech for survivability.
I actually was working on the same alike build as the Fire Destro+ SL poster by Darkonyx..

" Yeah about that deep affliction. PvP will take huge hit from lack of SL. Then again, its to be seen how will "Haunt" and more improved drains add up to survivability.

do you want cheapest wow gold? you can get wow gold here.