I love BookTV. Not as much as TorgoX, but it beats so much else on TV for interest. Right now I've been watching Michael Shermer (author of In Darwin's Shadow: The Life and Science of Alfred Russel Wallace: A Biographical Study on the Psychology of History). I'm amazed at how good a speaker he is. He speaks in complete sentences and has a really strong grip of the facts. He talked about the Darwin/Wallace parallel evolution of evolutionary theory, Wallace's spiritualism, and much more. Here's the blurb about the BookTV session. If you get a chance, TiVo it. Very cool.
--Nat