World of Warcraft Classic, the official "vanilla" server from Blizzard, is currently in development. The news comes via today's BlizzCon 2017 opening ceremony livestream, where executive producer J. Allen Brack was on hand to give the details.
Blizzard has been clearly been listening to World of Warcraft fans over the years. Access to legacy game content is something they've been clamoring for since the Burning Crusade expansion launched in 2007. It made serious changes to WoWas we knew it, making certain areas inaccessible to players, in addition to other significant alterations. When 2010's Cataclysm expansion debuted, it made further cuts that ensured new players would never truly be able to experience the same WoW that others did back in 2004.
Fans had been working on several solutions for the issue before, creating their own private "vanilla" versions of the game that reflected the way it was before the new expansions released. Blizzard had been shutting these servers down in the name of copyright claims, but it appears there could have been a secondary reason here, because World of Warcraft Classic has been in development for a while now.
There's currently no release date for World of Warcraft Classic, but we'll likely be hearing more about the server as we head into 2018. For veteran WoW players, the seventh complete expansion, World of Warcraft: Battle for Azeroth, is on the way as well, which will further explore the lore behind the rivalry of both Horde and Alliance factions.