Having played various MMO's as a rogue or a similar class of character I decided to go down this route.
Reasons behind my madness:
Assassin (41 points) - basic rogue build, improved stealth, improved / max poison stats (poison application, duration & damage) and max bleed capability. I did not put points into Improved Savage Strike as it would be a waste of points. Blinding Powder, Double Cross, Enduring Brew & Slip Away are nice skills to have at our disposal - however with my play style they are yet another waste of points that are needed in my other soul trees.
As you may have noticed by looking at the soul tree and from reading the above paragraph I did not mention Advanced Flanking. This is one of my situational passive talents. Depending on the situation / raid (and further progression in levels) I may end up taking the 2 points out of Physical Trauma and putting them into Advanced Flanking. I have yet to see the numbers parsed - obviously when I do I will come back and edit this portion of my build write up.
Bladedancer (20 points) - I went with Quick Reflexes, Combat Expertise, Blade Finesse & Ambidextrous for obvious reasons. Improved critical hit, dodge chance are a most for an assassin rogue. Having 50% improved damage from normal attacks, well everyone knows that basically half a rogue's damage is from normal attacks. Ambidextrous should be another talent that speaks for itself - an addition of 15% to dexterity only helps out the rogue class.
3rd Soul Tree - Optional - The reason I say this is optional (for myself) is due to the fact that at this point in time I have not been able to parse the difference between the added % to dexterity or Attack Power.
Saboteur (5 points) - I put 5 points into Nimble Fingers for an additional 15% to dexterity.
Riftstalker (5 points) - If I am to go this route then I will put 5 points into Unseen Fury for the 15% to Attack Power. Also, due to the fact that I am going DPS and not tanking there is no reason to go further up the tree.
I am open to any and all comments to this build.