What makes an MMO game social? It seems to me that there are a few ways to meet friends in games:
- Meet them out in the world, and join up with them to accomplish shared goals in the open world.
- Meet them waiting for, or matched for, an instance – dungeon or battleground – to accomplish the shared goal of that instance.
- Join a Guild, or whatever the game calls a group larger and more permanent than a party, and meet other folks in the guild that share the above goals.
- Meet them outside of the game, and come into the game together.
But once you bump into someone in the game, there are aspects of the game that encourage or discourage the formation of longer term Social Interactions in the game.