A few weeks ago Religion Dispatches published an article about medieval manuscripts and multitasking. The point is that for centuries our minds have referenced texts on multiple levels; the internet did not inherently create this distraction. There is also this gem from a David Brooks column:
The Internet-versus-books debate is conducted on the supposition that the medium is the message. But sometimes the medium is just the medium. What matters is the way people think about themselves while engaged in the two activities.