Macs and desktop publishing software replaced expensive typesetting equipment. But the expensive publishing software still runs on minicomputers, and the presses are still huge machines that distribute paper and ink using trucks and airplanes. The next step in the process completely replaces the publishing system software and the presses and trucks and airplanes. Production costs will go to virtually zero. Lead-times will go to zero too.
Time becomes a much more flexible element.
Some players won't keep up, and new players will enter. It's another publishing revolution, and it's even bigger than the one that happened the last time around. The web works now but we wonder about the future. Electronic transport mechanisms will evolve and change. If you're in the electronic publishing business, being able to easily try out new distribution mechanisms will make a difference.