My Rogue is the oldest character I have, and for as long as I can remember, rogues have been asking for Sprint to be on a shorter cooldown (and to balance it, have it last a shorter amount of time). Well, it looks like Blizzard finally thinks that this idea has some merit, because the new Shadowstep also acts as a mini-Sprint.
Sprint rank 3, learned at level 58, grants a 70% speed increase for 15 seconds with a 5 minute (3.5 minutes with talents) cooldown. This new mini-sprint grants a 70% speed increase for 3 seconds with a 30 second cooldown, in addition to the bonus damage and blink-like effect of Shadowstep. Between the 25 yards you can skip and the additional speed boost afterwards, you can cover some serious ground on a fleeing opponent. If that weren't enough, Preparation will also reset the cooldown of Shadowstep as of the next patch, allowing you to Sprint > Shadowstep > Prep and then blow Sprint and Shadowstep again immediately if necessary. Although this adds some much needed mobility to the Rogue class, the downside is that you have to spec heavily into Subtlety to access this new mini-sprint, so it isn't available to all rogues. Still, it's a step in the right direction.
Preparation is also being tweaked next patch -- it will reset the cooldown of Shadowstep, but it will no longer reset Adrenaline Rush. Unfortunately, this is quite a large nerf to the AR/Prep (0/31/30) spec which is popular in arenas currently. The power of a 30 second Adrenaline Rush combined with Hemorrhage and Mace Spec was a sight to behold, and while this change doesn't completely kill the spec, it does make it far less potent.
Ambush and Backstab are also seeing buffs next patch -- a 25% increase to the former (bringing it from 250% damage to 275%) and a 10% increase to the latter (bringing it to 160%). Sad news for Combat Dagger rogues, though -- the 10% damage increase to Backstab is only granted by taking the Sinister Calling talent, deep in the Subtlety tree.
Finally, Blizzard is still investigating problems with Vanish and Cloak of Shadows. There have been numerous reports of Vanish failing to apply stealth at all when activated, and Cloak of Shadows being ineffective against PvP opponents. Vanish has long been a pet peeve of mine, simply because it has never reliably worked 100% of the time. For a long time the devs have attributed this to server / client lag and have stated that there are some situations when Vanish can be broken due to latency (just an unfortunate limitation of current technology), but recently they've identified one issue with it and are investigating it. Although I wouldn't hold your breath waiting for a 100% guaranteed Vanish, the current issue(s) with Vanish and Cloak of Shadows should hopefully be fixed by the next patch, if not a hotfix earlier than that.