This post is mainly for Neveah altho it could prove usefull for others. Ok this things first, Specs:

As EVERYONE knows currently ShS(Shadow Step) is the most common build for rogues who intend to PvP, You have Cheat Death, Faster Cool Downs, Preperation, Premeditation, Better stealth, Better stealth Detection, Armor Pen and much more all in 1 talent tree

The "standerd" build for Sub is 20/0/41 tho the points can move around abit for personal preferance:

http://www.wowhead.com/?talent=fbe0ovZZxrfoMGRoxst

This is my current spec altho i plan to change it for:

http://www.wowhead.com/?talent=f0ebovZZxrfoMGRoxst

Reason for this is i NEVER use Evis, and if i do its to finsh my target and use my remaing combo points. Why not go for 20 in combat? well compaired to Assassination Combat is gimped, from assassination you gain 5% Crit, 60% chance to gain combo points on finishing abilitys, 25 energy when you use a finishing ability, 30% extra Crit Damage bonus and for arena 32% chance your poisons will NOT be dispelled!

Proffesions can be:

Blacksmithing
The MAIN reason you would chose this Prof is for the weapons, remember tho you can only use one type, Mace or Sword.

Mace: http://www.wowhead.com/?item=28439
Imba for MH and u can eaily get a offhand mace from PvP for 9k honor!

Sword: http://www.wowhead.com/?item=28427
Offhand Weapon

Remeber that Swords are more "reliable" damage where as macers are "spike" damage with both more and LESS damage then swords.

Engernieering
Helm: http://www.wowhead.com/?item=32478
Rivals T4 and gives extra stealth detection giving you the advantage over all stealth classers!

Belt: http://www.wowhead.com/?item=23825
Brilliant for "Oh Shit" Situations as a 4k shiled can realy turn the tides on a battle

Boots: http://www.wowhead.com/?item=23824
Tho they dont last long the speed boost is ALOT you can fly from 1 side of a arena to another in 2 seconds leaving everyone else miles behind.

Trinket: http://www.wowhead.com/?item=18638
Reflect Fire spells

Trinket: http://www.wowhead.com/?item=18639
Reflect Shadow spells (like Deathcoil )

Trinket: http://www.wowhead.com/?item=18634
Reflect Frost Spells

Granade: http://www.wowhead.com/?item=32413
Works the same as Freeze for a water elermental

Granade: http://www.wowhead.com/?item=23737
Ranged Aoe Stun