I have tried it a few times. It's good if you're new to the game. Otherwise not so much. I found I leveled slower by using it, as it's suggesting to take the longest possible route usually. Basically following roads everytime, when you could take an easy shortcut. Especially if the shortcut involves a bit of fall damage, it's out of question. The "go here" spots don't also update if you take a shortcut, and then the waypoint arrow points to wrong direction. But perhaps it has been updated since then.

Anyway, there are no more shortcuts. There are no more "Tricks". It's just straight questing now since Blizzard nerfed other methods of leveling. You can still do dungeon spam, it just won't be as fast. You can still do BGs, it just won't be as fast. Just about the only alternative way to level that rivals questing is Pet Battles(which makes ZERO sense).
Discipline: Premonition - Heals nearby targets within 20 yards for [ 75% of Spell Power ], and applies Atonement to yourself. Deals [ PS * BC1 ] Shadow damage to yourself for each Atonement you have active, and increases their duration by [ 5 + 0.1% of Spell Power ] sec. Holy: Rapid Mending - Prayer of Mending is now instant cast, and its jump range is increased by 10 yards. Shadow: Void Origins - Void Eruption is now instant cast. Rogue