There's an excerpt from Andrew Piper's "Book Was There: Reading in Electronic Times" on Slate that trumpets the tactile advantages of p-books, positing that "E-reading isn't reading."
Quoth Piper: "For Augustine, the book’s closedness—that it could be grasped as a totality—was integral to its success in generating transformative reading experiences. Its closedness was the condition of the reader’s conversion. Digital texts, by contrast, are radically open in their networked form. They are marked by a very weak sense of closure."
Aristotle, Braille, Delacroix and our favorite, El Lissitzky, also pop in.