At Liberty and Power, Steve Horwitz has a characteristically thoughtful essay about the implications of the Killian Memos flap for communications in society. He further elaborates on that here. I don't know that I share all his enthusiasm for the free market's challenge to major media. It will inevitably mean that more rumor will float among us, to be passed on and challenged as may be. But I think some of the most important commentary on the whole matter builds on the experience of art historians. Both David Nishimura at Cronaca and, in the commentary on Horowitz's essay, Evan Lowell Maxwell, a reporter on the west coast, make the point that forgeries in art are most likely to be accepted when they both fill a gap in an artist's oeuvre and conform to expectations. That may mean that we have to be skeptical, especially when a document tends to confirm what we already believe. Nishimura goes on to point out that, often, a fraud can be detected from a second hand copy of it, but a work of art or, by implication, a document can not be certified as authentic except from the original of it. To my knowledge, CBS has not claimed to have had the original documents in hand.
*Josh Levin at Slate has the best summary of questions regarding the authenticity of the Killian Memos.