I decided to spec to Shadowstep today and check it out. I have to say, it can be fun, but it is a PVP ability that sucks for PVP. There is really no purpose in having this for PVP because people are always moving around. you use it, you step, and the player you targeted has moved and now you have to chase him anyway. By then, the bonus dmg cd is gone and it's a wasted move.
I highly suggest you don't spec to this until they add something to it...like an auto ambush with bonus dmg on next hit for 5 seconds after you use shadowstep. Then it might be useful.
So I spent 45g on this respec, then another 50g to go back to mutilate. Maybe it's just me, but that is my take on shadowstep. It is not worth it.
I've heard a lot of bad news about this talent. I'm just glad sap is a tier 2 sub talent with only 2 points and it works 100% of the time now :)
Have you tried making a macro to shadowstep then ambush TB? This might reduce the time between stepping and attacking enough to make it worthwhile.
I noobed a bloodfang troll rogue with shadowstep yesterday. Even with his little hop there, I still stunlocked, DoTted, and CB evis'ed him. v76.