The second thought is really a looking-at-it-backwards inversion of one Martyn’s comments in his blog post Create Digital First:

…we are the start of a digital consumer offer but it is…based on yesterday’s physical cost model, processes and perceptions. Merely taking the finished book and generating a digital rendition that mirrors the physical one is what music did with CDs. Is it logical to merely replicate the book and create just another rendition? We don’t envisage the same demand change as music experienced in selling just fragments (tracks), but it is possible to see the selling of instalments or part works, where all the complete ‘book’ may not be bought.

Or looking at this another way, couldn’t the book be the fragment? I wrote a little while ago about the idea of extensibility, that books could be surrounded by, in William Gibson’s words, a ‘quasi-spectral hypertext’ that extends the frame of the text beyond the information contained only on the page. This is the kind of thing Harlequin are beginning to explore with their Enriched Editions.

So if consumers are open to new pricing models and new ways of configuring book content, especially fragments and parts of works, doesn’t it also stand to reason that the basic text of a book could be the fragment, and consumers pay a premium for enriched versions that have value-adds? This would bring it more into line with the DVD retail model of included special extras in limited editions. It would also help publishers to differentiate between general retail audiences and niche fan audiences.