When WoW Classic launches (Aug 27!) it will use a new tech for managing server populations called "layers". From BlizzardWatch:
Called “Layering,” the new system will help reduce queue times and improve server stability for the launch of WoW Classic. Layering is tough to explain without a metaphor, and thankfully Blizzard came up with a good one while explaining it to press and content creators recently.
Imagine a tray with an empty glass. The tray is a single server in WoW Classic. The empty glass is a layer. When you log into the game on launch day, you’ll be with a flood other players: the water that we’re going to pour into the glass. Once the glass is full, we add another empty glass and start filling it up with water, or players, too. Each new glass is a new layer that consists of two to three thousand players — which means any single server could handle tens of thousands of players at the same time but without all of them being crowded into the same place in-game. The only way to see players from another layer is to group up with them —otherwise they don’t interact.A layer is basically an invisible server. You get assigned to an invisible layer, and you only see other people who are assigned to that same layer. If you join a guild, you get transferred to that guild's layer. So you should see the same guilds and characters over time.
If the population of two layers drops down, the layers are merged, just like a server merge. Only because the original and final layer ids are unknown, and character names are unique across both layers, the merge should be unnoticeable. Other than seeing a bunch of new people running around Stormwind.
The interesting thing will be to see how many traditional "servers" WoW Classic launches with. Perhaps it's theoretically possible that WoW Classic could have a single server (or maybe 3 for PvE, PvP, and RP) and have 1000 layers.
Of course, naming characters would rapidly become very, very hard. And I wonder if there is value in having a named subcommunity, rather than everyone thrown into one giant pot. Is it good to feel like you belong on Lightbringer, while others belong to Skywall?



