In most games I play solo only because I get tired of having to listen to overly elitist / bossy players. The kind of people who map out every encounter in most MMO's and know step by step how to cheat through it just to finish it. If the people in this MMO roleplay then it will make anyone who likes pathfinder gravitate to groups. If they concentrate on stats and items etc then groups will become tactical and more like eve and you will see alot of solo crafters. The way players act about the game decides the level of interaction between strangers.