When content can be separated from delivery media, individuals will usually only pay for one of the two. This is the current dilemma of the phone companies. Now that conversation can be digitized and IP'ed, its worth is zero. Only the network carrying those bits has value. If I can 'FWD' or 'Skype' my friends and colleagues for 'free', why would I want to 'phone' them and pay? Brad Gibson's Current Thinking: I'll pay you once but I won't pay twice.
I'm looking forward to more on this from Brad. He identifies voice and music as two types of content that can easily be separated from the delivery media, and books as a type of content that can't be separated yet.