A recently-posted sentiment about the downside of reading books on screens rather than from a printed book:
Because they have been largely walled off from the world of hypertext, print books have remained a kind of game preserve for the endangered species of linear, deep-focus reading. Online, you can click happily from blog post to email thread to online New Yorker article – sampling, commenting and forwarding as you go. But when you sit down with an old-fashioned book in your hand, the medium works naturally against such distractions; it compels you to follow the thread, to stay engaged with a single narrative or argument. [As reading shifts to networked devices,] I fear that one of the great joys of book reading – the total immersion in another world, or in the world of the author’s ideas – will be compromised. We all may read books the way we increasingly read magazines and newspapers: a little bit here, a little bit there.
— Steven Johnson, from his April 20, 2009 Wall Street Journal essay entitled “How the E-Book Will Change the Way We Read and Write,” quoted by Nicholas Carr, in his January 25, 2010 posting to the Encyclopedia Brittanica Blog’s Learning & Literacy Forum.