Author Steven Johnson on what e-books are missing: "Skimming."

Skimming is the least of it. Current ebooks, in their linear form, are essentially the equivalent of 19th century horse carriages with motors. "Books" need to be reimagined. While reading is and will remain a fundamentally linear activity, there is no reason why books need to be.

For example: Why is text presented flatly? Isn't that a direct consequence of the limitation of physical paper? Where are the ebooks that allow you to dynamically fold text according to hierarchical order? In a mathematical text, say, sometimes I'd like to highlight the core results; other times, I want to home in on a particular result and highlight the "path" (i.e. the "helper thms" that are needed to establish the core result). Yet other times, I'd like to see the connection between results across sections _on the page_, i.e. without paging back and forth and holding everything in short-term memory. Sometimes I want the author's comments and discussion and "connective tissue"; other times, I don't want to see anything but the structure.

Apple did a good thing, a first step with the option to generate flashcards from your highlighting and notes. This is one extremely obvious thing that ebooks were missing, although I think the implementation is not yet very good, rather clumsy in fact. Sometimes I get frustrated that people keep making ebooks as if they were still limit to the same physical constraints as paper books. The whole form and structure and interaction could be made much more malleable, such that the presentation of ideas "adapts" to your brain rather than your brain adapting to a successive, linear, "rectangular", fixed presentation and compensating for it. It's not like "ebooks" simply means adding a bit of "multimedia" like it's the 90s...

But if I repeatedly press "next page", my Kindle doesn't do a full refresh on each turn. It's actually redraws the pages quickly enough to be skimmable.

I was thinking it would be cool (well, it might only work for me...) to have a "skim" mode on e-readers which let skip, say, 8 pages at a time - but the screen would be horizontally split into 8 sections to show the text from each of the 8 pages.

I only need to see a snippet of text to remind me "oh yeah, it was around here somewhere..." I should whip up a proof-of-concept to test it, I guess.

I read a lot of math too and the points you raise are good ones. I bought a Kindle DX in hopes of jettisoning a large part of my hardcopy math library; thanks to TeX, a huge swath of math literature is available by PDF (most of it free, if you have university access). I guess I wasn't prepared for how cumbersome it would be. Flipping back 10 pages to check a lemma takes, well, 10 seconds. It really detracts from the study experience.

That said, if I may play devil's advocate for a second, another way to look at the linear structure imposed by print is as a useful constraint for conveying thoughts in an effective manner. Every once in a while, I come across a "classic", math or otherwise, where the author has put so much thought into structuring her argument that I don't need to flip around. Invariably I absorb more from these rare gems than I would from a sort of hypertext arrangement, simply because somebody thought hard about the best way to learn the material.

It's funny you mention Apple because this strikes me as a very Apple thing to do--impose something on its users which initially seems quite cumbersome (one-button mouse, no floppy, one-button cell phone, no CD/DVD, hell the whole HIG), but actually turns out to be a clever mechanism for enhancing usability.

It's actually pretty disheartening how few e-reader-native e-books there are these days. Most of the e-books I read are simply reformatted paper books. The better ones -- and, anecdotally, I'd say these represent 5% of the e-books I own -- have hyperlinked chapters. It's pretty clear that the big publishers are still treating e-book editions as afterthoughts.

No doubt this will change. E-book consumption is rising rapidly, and it's abundantly clear that the e-reader/tablet/etc. is the future of the industry. But right now, the e-book is still in its infancy, and publishers haven't yet shifted their priorities in its favor.