World of Warcraft Classic is currently in beta, which means some players are getting a chance to experience a much older version of the MMO ahead of its release. WoW Classic is based on how WoW played in August 2006, back around update 1.12. Back then, things were different. Tauren hitboxes were much larger, sitting could cause certain combat effects to not trigger and completed quests were marked with dots and not question marks. Strange days.
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.
With the Classic beta now out it seems every related article somehow manages to spark the eternal war of "Vanilla was the best WoW sucks now" and "lol nostalgia goggles, Vanilla sucked, enjoy your two weeks of Classic". I have to say, even though I understand the principles behind the battle and the reasons people behave and talk this way... I actually REALLY don't get it on a deeper level.