This is totally late, but I was browsing unanswered questions.
PVP does not have a "rotation", PVP just has specific "priorities" and "situations".
Here's a brief rundown on Concealment:
1) Don't do anything to your target without Corrosive Dart. CD is not a good opener )in fact it is terrible) but it is vital to your burst. It allows your laceration to re-grant Tactical Advantage (TA) and it means your volatile substance can damage your attacker.
2) Stick to roots, don't stun too hard. As Concealment, you have....a lot of roots. Using stuns will build too much resolve, and your target will become immune. The 3.2.1 update will rework resolve, meaning after your opponent is white-barred, they will just be snared. Waste of stun in that case.
3) Open from Stealth for optimal burst damage, but, use cloaking screen as much as you need, but don't get too hung up on it.
4) Try to have two Kolto Probes ticking on you (actually just 1 at 3.2.1) during long combat phases such as node offense/defense. Losing a GCD for those during a duel can be fatal, but having those extra ticks if you can spare it, will heolp a lot.
5) Learn to use your roll, it is your best friend. It grants Doge/Evasion while you're rolling, so you can mitigate a lot of damage, like from a Sage or PT.
5a) Practice getting double-roll proc. If your initial roll lands you on a platform (like a rock or the huttball platforms) it will trigger another roll.
For prolonged fights, keep your Corrosive Dart on your target, apply Vol Substance every chance you get, and alternate between Veiled Strike and Laceration as cooldowns and TA permit.
Only use your Crippling Slice to pin your target if you can't get behind them. Only get behind them for Backstab.
As for opener....
Kolto Probe (if you can) + Stealth + Backstab, Laceration (a.k.a. Stab), Vol Sub, CD, VS, Stab, Stab, Stab, Root (any), Backstab. Rinse, repeat, kill.