Recently 2 of us rogues switched from armor pen ( that I liked) to the agility / haste combo that was suggested by the Rawr program and backed up by Simcraft ( agility being the most important stat per it's results)
The issue here though is Sindgragosa.
Basically, you get a de-buff from the boss that stacks every time you hit the boss, go past 5 stacks and you are likely going to die. The way to get this de-buff off is typically to stop attacking at 4 or 5 stacks and wait for it to drop off (it adds a stack and refreshes it's full duration if you attack while the de-buff is on you)
With agility and haste based dps you use a great number or fast attacks with less damage per each attack, armor pen and attack power based dps uses less attacks but does more damage with each attack.
If the de-buff is allowing you to get 4 attacks and than stop, it seems to both of us that the armor-pen and attack power based rogues have a much better dps output.
One fight isn't enough to warrent a change of your dps set-up, BUT, if you are deciding between specs when you hit 80 and start to get geared up you may want to weigh this in your decision process.