Because reading is an act of translation—taking seemingly random scratches on a page and turning them into a story in your head—a book is, more than any new media, a cocreation of reader and writer.
And as reading changes, that mustn’t change. We must preserve that magical moment when the space between you and me evaporates, and we are all of us making a story real together. Bells and whistles are all fine and good, but the writer must not leave the story behind, and the reader must not be allowed to abandon her responsibility as cocreator: she, and she alone, can make a story real.