I think that GH will still be the default campaign world. I'm now playing 3 campaign, one epic in the FR&Planescape setting, one middle in a world of my own, and one low level in FR. I would like the core books contain as less information about any campaig world as posible. I know that something must be in (like some gods), but I would like see it that way, as was Rolemaster. I played Rolemaster for years in the world of Conan and was one of the best campaign ever...