Is there a market for campaign worlds?

I just wanted to throw the question out there. I could be wrong but my perception is that the one product that old-school gamers desire least of all is a campaign world. Does that seem accurate? How interested are you in published campaign worlds, and what would one need to be like to be of interest--in terms of presentation and originality? Do you prefer straight up typical fantasy or does a world need a "twist"? How far is too far when trying to be "original"? Just testing the waters.