Short form posts

Interesting that Amazon now sells short books, some under a hundred pages. I wonder if that's a good thing? Is there something special about the 300 to 500 page book form that we're losing. Has Twitter and instant messaging caused us to lose a valuable ability to sit still for long periods. How does this affect my team's ability to write long-form test plans, and understand lengthy design documents. Is this the end of the world? :)