There's an article from the RAND Corp by John Warren called "Innovation and the Future of e-Books" that you can read for free. It's admirably succinct and for the most part seems pretty reasonable though not quite reasonable enough to be believable. Let's start with:
* It's a bit too tech-future gung-ho. When talking about responses from Frankfurt attendees he derides their "head-in-the-sand thinking" apparently just because they don't see a shiny future in e-books. (It's worth pointing out that though the specific numbers create the illusion of statistics these are really just poll answers - there's no extrapolation, no hard data.) The next paragraph says they (or at least the publishing business) should be learning from the music business but that's an odd statement. He doesn't point out that the decline of music labels can be directly attributed to their mishandling of first CDs and then downloads. His comparison to the music business finding other revenue opportunities seems barely applicable to the book business or if it is then he needs to do something more than pointing out what the music business has done (one of which - "sales of single songs" - is in fact the oldest type of music revenue).
* He assumes that enhancement is actually an advantage for books. The most extreme is mentioning an e-book of Pride and Prejudice that includes a filmography, reviews, recipes and illustrations, apparently oblivious that a regular book can do exactly the same thing. Norton Critical Editions is the most thorough but hardly the only example. In fact, all these "enhancements" aren't necessarily enhancements - in the textbook market price is actually more important. (And for anybody reading this who doesn't know me personally, that's my day job so I'm very familiar with it.) I'm not saying this stuff shouldn't be there but it's not necessarily a bonus.
* The example of RAND's own I Want You with a DVD of primary source materials isn't appropriate for the regular book market as he seems to realize later. 2300 documents isn't an enhancement, isn't even much of an object. You'll have to be far more than even strongly interested in the subject to even have a use for that, possibly without experience in handling or interpreting such material it might even be a barrier.
* Warren later uses the buzzword "mash-up" to mention "combinations of disparate bits of digital video, audio, text, and graphics refashioned into something new" while again assuming that this is a good replacement for traditional books. While I certainly would like to see things like this, they will be something different. Plopping all this stuff on top of Madame Bovary or Gravity's Rainbow (or you shudder to think, Pound's Cantos) can't in any way improve them, can actually only distract. And yes I do find the books glossing Gravity's Rainbow and Zak Smith's visual response to be worthwhile but they're secondary, optional sources.
* The Book of Disquiet isn't a novel and doesn't exactly "play with hypertext form". It's actually more like Leaves of Grass or Aubrey's Brief Lives that doesn't exist in anything like a final form, leaving an enormous amount of organization and sorting up to the editor. I'm guessing most readers go through editions of these books front to back even when they're aware of the background. (And even though Warren wasn't aiming for completeness how could he leave out B.S. Johnson's The Unfortunates which was recently reissued?)
* For that matter when discussing hypertext did he omit computer games because they aren't purely text? (Guess Infocom is too long gone to count.) These fill the "choose your own adventure" model more than any book did.
* Hypertext has its limitations for a much more fundamental reason - most of us don't have any reason to do the work to create something of lesser value. I can write a sonnet but I can't write anything like Shelley's or Donne's but even if I could that doesn't mean I wouldn't want to read theirs. I can follow some hypertext story or remix a song but in the end it's extremely unlikely that this is as satisfying on any level as reading a completed story or hearing a finished song. Anybody who's ever listened to an entire album of remixes knows this is true. That's why I mentioned computer games above. The assumption with hypertext and remixes is that the mere fact of hypertext and remixing has its own value but computer game creators know there has to be a reason. This is hypertext in the pretty limited area Warren starts with - once he moves to the Web, Wikipedia and so forth hypertext is different because it actually does have a purpose. (Though if you've ever stumble on one of those sites that links almost every noun to someplace else you'll realize there are limits - even Wikipedia is guilty of this when it links years.) Warren seems to think wikifiction is a good or at least interesting idea - I find it almost impossible to expect anything worthwhile to be created that way. There are after all several round-robin novels from at least the late 19th century onward and none of them are anything more than curiosities.
* Warren does mention that e-books are a solution without a problem. Sure they're going to be more prominent but for the moment they're more expensive, more fragile, less stable, harder to read and perhaps simply inferior. Some or most of this will be resolved--I don't expect us to shift to Kindles or Sony Readers so much as see a convergence of readers with computers instead of separate dedicated devices--but it's far from foregone that e-books will replace physical books. Music was always independent of technology as far as listeners were concerned - in just my lifetime we've had LPs, 45s, reel-to-reel, 8-tracks, radio, Internet radio, CDs, MP3s. Shifting was easy, especially when MP3s offered a clear and present advantage (and certainly some disadvantages such as sound quality that most people didn't particularly care about). The situation with books isn't that we haven't reached such a tipping point but that while lots of commentators think that we will, nobody can exactly envision what that might be. The most likely outcome seems to me that e-books will become an additional form alongside print, perhaps the place for those deluxe enhanced editions or maybe the best way to read more ephemeral books like self-help, how-to and most political books (I'm not being snide - political books date extremely fast as anybody who goes through thrift stores or library sales can attest). Let's all gather back here in 2019 and see what happened.