I've already got a few books on CDrom, so we're part of the way there. They are not as comfortable to read as a regular book - at least not for long.
I would guess there's a few things to iron out yet, such as:
A) Making a 'reader' that's cheap enough, light enough and robust enough to compete with a traditional book for ease and comfort of use.
B) Sorting out the copyright and protection issues. The CDrom I have is a collection of "500 Classic Works of Literature" - in other words 500 out of copyright texts. <img src="/ubbthreads/images/graemlins/biggrin.gif" alt="" />
Printed books and software are currently dealt with in 2 completely different ways. Teachers who buy books don't expect to have to buy a site licence to read the same book to several classes of kids for instance. Books are freely lent in libraries (which even provide photocopiers to make it easy to duplicate the bits you want. There is supposed to be a page limit per book, but I've never seen it enforced). Unlike books, End User Licence Agreements for software usually seeks to prevent hiring, multiple usage, second hand sales, and even (in some instances) giving it away. Completely different from the way we view books.
Publishers would not want electronic books to be easily copied, pirated, swapped etc so I expect we'll have all the same clumsy copy protection issues to deal with that crop up with games. <img src="/ubbthreads/images/graemlins/disagree.gif" alt="" />
Didn't Stephen King try selling a book over the internet, downloadable chapter by chapter? Did I read somewhere that he abandoned part way through? Anyone remember that?
Some interesting potential though. <img src="/ubbthreads/images/graemlins/think.gif" alt="" />
