Servers
From Drunkapedia
All of the severs allow players to be Player Killers, Darktide is exclusively PK, the other servers default to Non Player Killer and also let players do Player Killer Lite.
Live Worlds
Darktide
Frostfell
Harvestgain
Leafull
Morningthaw
Solclaim
Thistledown
Verdantine
Wintersebb
Beta Servers
Blue
Green
Red
Test Servers
Shadowclaim
This server was available for all players from ??/??/?? to ??/??/?? to stress test some new server hardware. The character database was an exact copy of Solclaim, hence the name Shadowclaim.
Throne of Destiny Open Preview
This server was available for all players from ??/??/?? to ??/??/?? as an open preview of the upcoming expansion pack Throne of Destiny. The character database was an exact copy of Leafcull.
Internal Test Server
As mentioned in numerous posts by developers, Turbine has an internal test server. It is currently not available for players.