I know we have other tools for mobility/snaring, but the thing is, we're still taking a net loss. We've had all of those tools before; the only new thing is Paralytic Poison, and if we take that, we can't use Crippling Poison. You mention that the level 60 tier gives us mobility tools, but remember that Subtlety already has two of the three talents, so we're going to lose either Prep or ShS.

So in the end, we get a little bit more ease at using Deadly Throw what with Shuriken Toss (although both of them are only a 30 yard range and most of the other ranged snares are 35 or 40, so it would still be possible for someone to keep us slowed without us being able to attack them), and we lose Prep or ShS (or both, if you take Burst of Speed, but then you gain that). Paralytic Poisons's not going to be very useful in a kiting situation, because you have to be able to reach 5 stacks for it to do anything, and if you can't hit the other person, it's worthless, whereas if you hit them only once or twice Crippling is immediately beneficial. The only real gain in mobility that I see is that Cloak of Shadows is now on Preparation as well, which is huge, but once again, you're still losing out on ShS.

I'm not saying rogues are getting nerfed into the ground or that we'll all of a sudden be terrible in PVP; I think we'll still be a force to be reckoned with. But there's no denying that we're getting a slight-to-moderate nerf in terms of mobility and snares (two sides of the same coin, one just affects us and the other, our enemy).