Update: There is a vastly superior review of the Schultz biography here, at the New Yorker magazine online, and featured on today's Arts & Letters Daily. The review is an outstanding example of analysing comics effectively, substantially yet without ponderous pretension.
The often-intriguing relationship between comic character and comic creator is treated informatively in this review on salon.com of a new biography of Charles M. Schulz, creator of Peanuts, Featuring Good Ol' Charlie Brown.
The biography is Schulz and Peanuts: A Biography by David Michaelis. I have not read the biography, but the writer of review comes across with a naively idealised view of humanity -- effectively blaming her childhood idol for lacking Sainthood.