Ok I have been 70 for a bit, and over the past few days have been pvping (is that a word?) here and there. First off I still have a lot to learn about the class in pvp, but I have a long way to go I am sure. This certainly doesn't make me an expert by any stretch of the imagination. But I thought I would share my thoughts so far.
Deathcoil is every bit the "I win" button I thought it would be... in the right situation. Combination of felhunter and deathcoil (when it's up) gives an excellent 1-2 punch that will finish up any fight with a ranged caster (provided I didn't get 2-3 shot by a 3 minute mage)
Also, against any non UD character seduce + nuke is still a nice opener... especially when followed up by a DC as an "I win" finisher.
Against rogues who get the opener, I pretty much always die... unless I get help. Stun lock ftl

I don't bother using DC when I have been stun locked and I get that little breather. Pretty much I am toast, and I just accept it. The only cooldown I will pop is ihot (instant howl of terror), to try and turn the tide. Most of the time they are either UD, or have a trinket so it does no good.
Warriors who know what they are doing just tear me apart, so I don't bother wasting my DC cooldown on them either most of the time... unless I get the opening shot(s). If I manage to get the opener, it can help turn the tides against a rogue/warrior... but only if it's close.
As others have said, fear is almost worthless since it seems like in BGs just about 1/2 of the horde is UD.

I rarely use it, outside of ihot.
My most hated ability these days: Cloak of Shadows. Rogues already had the huge advantage against any warlock they could open up on... now basically they are unbeatable unless you have insane amounts of stamina and can outlast their initial stun lock, and still have enough health to last through a counter attack. It seems like I would need a huge amount of heath too.