Rather than attempting a narrative, I'm just going to jot down what's in my brain about digital publishing and the future of the publishing industry. (These are just my opinions - I have not made a scientific study.)
1 - E-books and e-readers
In the thinking and talking about how to price e-books and why people may want e-readers instead of or in addition to print books, there are a couple more things to take into consideration. Namely, that there are some of us who love, love, love print books who are also concerned about the dead-trees aspect of print books and look on e-books as a tree-friendly alternative. Also, when you buy a print book that's the total cost of that print book. When you buy an e-reader the initial cost per e-book is high because it's measured against the cost of your e-reader - if you buy a Kindle for $189 and your first e-book is $20, you're essentially paying $209 to buy that e-book. Obviously the cost of the e-reader is amortised over time. But those who are setting the prices should realise that part of the squawking about the cost of e-books is to do with the fact that readers are paying for e-readers and they don't then want to pay a lot for e-books on top of that.
2 - Authors and covers
Once all the publishers' backlists are digitised and there are thousands and thousands and thousands of e-books available, will covers for each individual book matter any more? Perhaps not. Rather, the author's brand may have more significance as a visual cue. Just like the old wax seal on an envelope, the author's personal brand will identify their e-books as a product of their (electronic) pen, so if you're an author you may wish to think about developing a visual brand - a logo or something like that. This brand can be applied to your e-book covers or could be used as a template that can be modified slightly for each e-book, thus providing an instant visual identification for your e-books. Or maybe I'm just trying to create work for graphic designers.
3 - The future is now
I often feel like there are quite a few folks in publishing who are collectively like a person who's been told the winning Lotto numbers and failed to submit an entry in time, and is about to complain long and loudly about their loss. We've had years to watch the music industry go through this; we can't say we weren't warned. Radiohead's little experiment with In Rainbows should be noted - and noted hard - as an example of what a big-selling author may decide to do some day soon. If blockbuster authors go it alone there will possibly be a period of calibration during which new authors won't even get a look-in at publishing companies, because there just won't be the money around to invest in them, but eventually we'll all need new stories from new people. If for no other reason than, to be blunt, people die (and I'm thinking of the industry in twenty years' time, not necessarily next month or next year).
4 - We have failed our teenage readers
There are so many excellent books for young adults - there have been for years. If the publishing industry (that includes me, by the way - I am not standing on the outside looking in) had looked at teenagers purely as customers and thought about how to retain them, I wonder how differently we'd have done things. I don't actually think we publish books that carry our teenage readers through to their thirties and forties and beyond (given that many non-genre novels are published for those latter age groups) but I'd be happy for someone to give me evidence that I'm wrong. It just seems that once YA readers are in their twenties they're on their own, and many of them stop reading - the rapture of their teenage years has gone. It's no wonder speculative fiction captures so many young readers - because it provides the rapture - but in the general fiction world I'm struggling to think of a concerted effort to publish stories for young people once they're over the age of eighteen. These are the very people whose worlds are now mostly digital - these are not people who are going to want print books in ten years' time. And as Clay Shirky said, 'No medium has ever survived the indifference of 25-year-olds.' Today's 15-year-olds will be 25 in a decade. Think about the teenagers you know and how they interact with culture - it's mostly digital, isn't it? That's what's coming; these are the readers we need to be thinking about and planning for right now.
5 - And finally
This is an interesting read: http://paidcontent.org/article/419-why-online-retailers-will-squeeze-out-publishers-in-the-book-business/