What's next? We've already seen the beginning.
1. Tube sites will pay surfers to upload their collections, it's already being done.
2. Video hosting sites like rapidshare which are just ways to upload paysite collections and link em on porn sharing forums are paying surfers to upload and get others to download:
http://www.storage.to/earn
At some point something has to give. There will be a point where producing porn won't be profitable, at this point a service like apple's itunes for porn needs to come in to make things profitable again.