An update to my posting on Kelly's article ("Nothing New Under the Sun").
If you are interested in a historical perspective on the impact that new media can have on the processing of information and the production of knowledge, the best place to go is to the work of Ann Blair who is working now on a project on what she calls "information overload in early modern Europe."
For the popular version of her work, see this Harvard Gazette article.
One of her early papers on the subject is posted at the Princeton Center for the Study of Books and Media site. (Scroll down to conference papers to find hers.)