Subtlety
We're going to make Dirty Tricks baseline.

We still think the mobility between Subtlety and the other trees is a little far apart. This is something we want to address.

We also think Subtlety's damage against heavy armored targets is probably a little low and we're looking at that as well.

However, as we said in the Twitter dev chat, if you had a tree with Assassination's burst or Combat's timers *and* Shadowstep and Prep, why would you play anything else in PvP? In PvE, we want to get all 3 rogue specs to be as close together as possible. But part of that involves Rupture and Honor Among Thieves, which are just more potent in PvE than PvP. In PvP, we think it's fair that Subtlety does less toe-to-toe damage given that the tree has so many advantages when not toe-to-toe. (Source)

Sprint cooldown
I will admit that the 3 min cooldown on Sprint feels a bit antiquated. It's something we're discussing but it's too soon to promise anything.