Via Clay Shirky:
Can someone make money by blogs? Clay Shirky in his article says that blogs essentially destroys the intrinsic and extrinsic values of Print Publishing.
Intrinsic -
It takes real work to publish anything in print, and more work to store, ship, and sell it. Because the up-front costs are large, and because each additional copy generates some additional cost, the number of potential publishers is limited to organizations prepared to support these costs.