As previously mentioned, Player vs. Player may be a touchy subject and there's not one standard spec that is used by all PvP Rogues. Now we want to talk about the talents in the three trees such as Assassination, Combat and Subtlety specifically have PvP flair to them and let you decide for yourself what suits your individual play-style. 
   Assassination, unlike the other two trees, most of the PvP related talents are located lower in the tree. If you want the PvP goodies that this tree offers, you'll need to make it your primary tree or use a hybrid spec.
Vigor increases your maximum Energy by 10.
Vile Poisons increases the damage dealt by your poisons and Envenom ability by 20% and gives your poisons an additional 30% chance to resist dispel effects. This isn't a particularly strong PvP talent, but it is worth noting as the 30% resist dispel chance could buy you a few seconds that you might not otherwise get.
Fleet Footed reduces the duration of all movement impairing effects by 30% and increases your movement speed by 15%. This does not stack with other movement speed increasing effects. It really is a shame that this is so far down the tree.
Crippling Poison is one of the best tools a PvP Rogue has to keep ranged opponents in melee range. With this, you can use Wound and Mind-Numbing poisons and still proc Crippling poison.
Deadend Nerves reduces all damage taken by 6%. While it may not sound like a lot, 6% damage reduction can be the difference in you living long enough to get heal or not. If you're this deep in the Assassination tree already, you should get this.
When it comes to Combat, it offers a wide variety of PvP talents, and many of them are located in the first 4 tiers which makes it a good choice for your left over points if you go deep into a tree and an even better if you want to use a hybrid spec, with half of your points in Combat.
Improved Gouge increases the effect duration of your Gouge ability by 1.5 second.
Deflection increases your Parry chance by 6%. This isn't the strongest of PvP talents, but it does have its uses. If for some reason you find yourself in prolonged melee combat, the parry could save your life.
Endurance reduces the cooldown of your Sprint and Evasion abilities by 60 seconds and increases your total stamina by 4%.
Riposte is a strike that becomes active after parrying an opponents attack. This attack deals 150% weapon damage and slows their melee attack speed by 20% for 30 seconds.
Improved Kick gives your kick ability a 100% chance to silence the target for 2 seconds. A clear choice for PvP, the 2 second silence effect can devastate another team if used at the right time. Between this and your stuns, you can make it near impossible for a healer to cast heals.
Improved Sprint gives you a 100% chance to remove all movement impairing effects when you activate your Sprint ability.
Lightning Reflexes increases your Dodge chance by 5%
Blade Twisting increases the damage dealt by Sinister Strike and Backstab by 10%, and your damaging melee attacks have a 10% chance to daze the target for 8 second. The extra damage is nice, but for a PvP build, the daze effect would be your reasoning for taking this talent.
Nerves of Steel reduce damage taken while affected by Stun and Fear effects by 30%.
Throwing Specialization increases the range of Throw and Deadly Throw by 4 yards and gives your deadly throw and Fan of Knives a 100% chance to interrupt the target for 3 seconds
The Subtlety tree can greatly enhance our Stealth ability, amongst other things. Like Combat, it works great with another tree as a Hybrid and has enough low level talents to use after going deep into another tree.
Master of Deception reduces the chance enemies have to detect you while in Stealth mode.
Sleight of Hand reduces the chance you are critically hit by melee and ranged attacks by 2% and increases the threat reduction of your feint ability by 20%.
Dirty Tricks increase the range of your Blind and Sap Abilities by 5 yards and reduce the Energy cost of your Blind and Sap abilities by 50%.
Elusiveness reduces the Vanish and Blind abilities by 60 sec and your cloak of shadows ability by 30 sec
Ghostly Strike is a strike that deals 125% weapon damage and increases your chance to dodge by 15% for 7 sec. 
Serrated Blades cause your attacks to ignore 640 of your target’s Armor and increases the damage dealt by your Rupture ability 30%
Heightened Senses increases your Stealth detection and reduces the chance that you are hit by spells and ranged attacks by 4%.
Preparation finishes the cooldown on Evasion, Sprint, Vanish, Cold Blood and Shadowstep abilities when activated.
Cheat Death is a great ability. While it can't prevent you from dying in all cases, it can keep you alive long enough to receive heals, or give you the time to finish off a badly wounded opponent before they do the same to you.
In a nutshell, there're enough talents in each tree that allow Rogues to tailor their Spec to their individual style.