There are still bucklers in game, but they are labeled as 'Shields'. Rogues and Hunters could use bucklers, but they later removed them, and Rogues/Hunters couldn't equip shields anymore. At the beginning, there were shields and bucklers.
During original WoW alpha, Scholomance was supposed to be an outdoor elite area (probably where Sorrow Hill is now), but the developers made it so big and good that they decided to make it an instance.