Useful for night elfdruids, it allows for a short trip to Rut'theran Village, serving the function of a Hearthstone for their hometown. Not so much for Tauren, since the trip from Moonglade to Thunder Bluff, even if free, takes almost seven minutes. (It used to be a longer ride over Darkshore that took 10 minutes, but now you get the direct way through Felwood). If you have the adjacent flight points, it is best to leave from the non-druid flight-path, close to the bottom of the region, and take the shorter trip to Orgrimmar.
With the advent of The Burning Crusade, this spell becomes slightly more useful, since it allows instant Azeroth, and from Moonglade you can easily find a transport to a capital city.
This spell is extraordinarily useful during the leveling process. Every even-numbered level the druid is ready to learn new and better abilities. Set your Hearthstone at an inn in the area where you're leveling, teleport to Moonglade, use the Moonglade druid trainer, then hearth back. This potentially saves a signficant amount of travel time.
Although extremely painful and time-consuming, the location of Moonglade can also give Druids a 50-level head start into Winterspring, via "corpse hopping". Once the Everlook flight path is discovered, interaction with the Timbermaw may be skipped entirely.