For big MMOs that cater to all the myriad playstyles, let’s ditch arbitrary server selection and instead come up with a model that works based on preferred styles of play.
Timmy likes PvE, Jimmy likes crafting, Joan likes PvP, Edward likes crafting but hates PvP, Dave thinks that PvE is a waste of time but loves to participate in the PvP and economy. Out of these five players, zero of them can make a meaningful decision about what server to join when they’ve first logged into a modern MMO. PvP-flag indicators do far too little to help people decide where to settle if flagging is even implemented—most games don’t bother—and roleplaying designations have even less meaning. Given only a list of server names there’s no way to make a meaningful decision of what server to join—a decision that can make or break a player’s in-game experience.
Let’s find ways to make server choice work better for the new player.
If the player has friends already in-game on their first log-in, let them provide the names of their friend’s characters and/or what guild their friends are in, and the player will be shuttled over to the appropriate server.
When an experienced player signs up for your MMO, give them a list of playstyles and ask them to rank them on a hate-dislike-neutral-like-love continuum (or have the player rank the playstyles from most preferred to least). With responses to five or ten such questions, you can gather enough information about the player to put him or her in a server with people with whom he or she will actually enjoy playing.
For inexperienced players, ask them questions about what kind of activities they would want to do in game with language that is newbie friendly. “Do you want to make the weapons that your friends use as they charge into battle?” instead of “Do you like crafting?”
Use this information to put people on servers where they can easily meet like-minded people and have fun. This doesn’t mean segregating all the various playstyles, it means integrating them where they are compatible and separating them when they are incompatible. If someone really hates getting ganked, don’t put them on a PvP server. If someone wants to craft and doesn’t mind PvP, put them on a server with other crafters—or put them on a PvP server that’s short on crafters.
A small amount of time spent gathering player preferences can lead to huge dividends when players find friends faster and get hooked sooner. There’s no reason to make player’s fire meaningful decision in game be a blind decision.
EDIT: Dblade, in the comments, suggested a better alternative to a Q&A with the new player. He suggests a Oblivion-like tutorial that allows the player to show their play-style through actual play. I think this is a great idea, though it can't sufficiently judge if the player likes PvP and crafting. A tutorial where the game learns the player's preferences coupled with a few simple questions before the player dives into the full game will greatly increase the chance of the player dropping into a community in which he'll want to take part.