Deep Blood PvP spec issues with subspec choices:

Blood PvP spec:

Couple things to note:
Early unholy talents compliment deep blood very well for pvp, at least for the first two tiers.

Unholy Tier 1 with this spec.
A) Vicious strikes is a great dual purpose talent for pve/pvp in just about any scenario.
B) Morbidity follows suit. Great dual purpose tanking/pvp talent as blood spec with sudden doom plays well with any talents that improve deathcoil. This is double true if you pick up lichborne.
C) Anticipation is really 100% for PVE tanking.

Overall, Tier 1 Unholy is fantastic for deep blood pvp.

Unholy Tier 2 with the same spec.
A) Epidemic is ok, but hardly required. With many various ways to remove diseases (some effortlessly via abolish disease and disease cleansing totems), banking on each application of disease lasting the full 18 seconds isn't a good strategy. Mostly a PVE talent.
B) Virulence grants dispel resistance, which is fantastic for pvp. Given that our diseases are less spammable in our assumed rotations than rogue poisons, and far, far less spammable than warlock dots, it's going to make virulence either nearly required against some classes (paladin, with no brainless way to remove diseases other than 1 disease per cleanse), or almost seem like a waste of points (shamans and priests). Given all the factors, I'd say that virulence at 30% dispel resistance is probably not going to be enough against the classes that we need it most against. I've played my hunter enough to know that going against well-played (this is key) shamans can seem like having improved stings is a waste of points, as poison cleansing totems seem to strip them off immediately anyways. The jury is still out on this talent for me right now.
C) Unholy Command seems like a talent that will be just as required for pvp as imp intercept is for warriors on live right now. I imagine this talent being just absolutely required for competitive pvp, but for right now(on the not-so-serious beta), you can get by with skipping a point or two in it.

Unholy Tier 3 with the same spec.
A) Outbreak only becomes a pvp-centric talent if you pick up scourge strike (similar to glacier rot in frost in tier 1, that it sucks without howling blast and frost strike), otherwise, primarily a tanking (AOE threat) talent.
B) Necrosis is OK, but nothing that I would really call required for pvp. It does help melt through heavy armor targets, though..
C) Corpse explosion. Fun in battlegrounds, but useless in arenas. A lot of fun to use while tanking! :)

Early frost talents are even better for deep blood pvp spec. Here's why.

Frost Tier 1 with the same spec.
A) Imp icy touch is useful, but not required. The 30% damage boost does stack nicely with the new bloody vengeance, but it's not nearly as useful as the new toughness.
B) Glacier rot I've already covered. Not really a good talent unless you're at least 31 points deep. This is a pretty weak Tier 1 talent overall, and should probably be just rolled into Rime.
C) Toughess is just fantastic for PvP. 50% reduction on snares, AND 15% more armor? Wow. This is the no brainer talent for pvpers, which sucks, because it means there's a lack of choice in this tier.

Frost Tier 2 with the same spec.
A) Icy reach is a no brainer. 30 yard range chains of ice is completely awesome.
B) Black Ice probably needs to be reworked as it's giving too much bonus to both frost strike and scourge strike. I'd probably change this to 2/4/6/8/10% increased crit chance with shadow and frost abilities. This makes it still appealing to both spells and frost/scourge strike, but gets rid of another unneeded multiplier which is currently making up some ridiculous damage. Good talent for pvp overall either way.
C) Nerves of cold steel I don't like, as I don't dig the dw thing at all for dks. It's fine for pvpers that choose to go that route I guess, though.

Frost Tier 3 with the same spec.
A) Icy talons is only really good if you're going deep into frost for either more synergy via killing machine, or you need to buff a raid via the group haste talent. It's not really a great choice for pvp as a last pick filler.
B) Lichborne is obviously good.
C) Annihilation I don't care for as a design philosophy, simply because I don't think obliterate does enough damage to warrant disease removal to begin with. I only picked it up for 3% crit for frost strike for a while, but then later just dropped it once I found out how good killing machine becomes later with haste talents, gear, and unholy presence.