Positive attitude; no discrimination; and whatever happens in game is handled in game, and if it can't be handled in game, then the GMs need to handle it and not the peanut gallery. The only persistent world I was ever involved in was during the age of MSN chat, and the Yahoo chat RP community self-deemed Eden at the time. Every situation that happened between chatrooms, which were realms and kingdoms at the time, it was settled in game with an actual army comprised of players. The more actual players you had under your banner, the stronger your kingdom was. It was very successful because everyone stayed in the illusion of the game, and those who couldn't were simply removed.