So, I distinctly remember when playing my rogue in retail that the shadowstep ambush opener was pretty much the best way to engage an opponent. I have looked up the ability and saw it was added in BC, so I'm sure it is in WOTLK. However, I have seen no one reference it on the forums, I do not see it in a talent tree, I do not see it in my untrained abilities either. How do you get shadowstep/when do you get it? I am very confused.
Subtlety, requires 40 points. And no - Shadowstep + Ambush is not a good way to open on someone, as you can always just walk up to him. You want to save Shadowstep for when your opponent tries to get away from you.