I'm not so sure about ebooks taking over the other classes of publication any time soon. We have had the technology for a couple of decades now. For example, university researchers have been reading papers as PDF or PS documents and many government documents have been provided as PDF or DOC (gack!). Reading on computers may have been inconvenient, but we knew how to create richly formatted documents and many richly formatted documents were available as soon as tablets emerged as viable ereading devices. So why haven't we seen the emergence of a bookless world?

Maybe there hasn't been enough time to make the transition. Maybe we have to wait for habits to change among those who are accustomed to the world of paper. Maybe the technology is almost there, but we have to discover that final touch. Maybe the current business models are holding us back. Or maybe, just maybe, we will never leave the print world behind. Maybe there will be some sort of balance between e and p.

Keep in mind that the MR crowd is extremely biased. A huge chunk of us are biased towards technology of any form. Those who aren't are still attached to ebooks. We may be a sign of things to come, or we may just be outliers.