The family of Don Markstein is reporting his death at age 65 due to respiratory failure following a prolonged illness. Don was a mover 'n' shaker in science-fiction, animation and comic book fandom in the sixties and after. I believe I first met him in person (as opposed to the correspondence which preceded that moment) at the World Science-Fiction Convention in Los Angeles in 1972 and even then, he had a lot of friends and a lot of respect within the fan community.
Don and his wife Gigi founded Apatoons, an amateur press publication that was reponsible for much scholarship and research about the field of cartoons, and Don edited the magazine Comics Revue as well as several books on comic history, including The Prince Valiant Companion. He also wrote a number of comic books, including Disney comics that were primarily published overseas.
His most lasting contribution on the 'net is The Toonopedia, which he updated every day since he established it in 1999. Until recently when illness (I assume) caused him to miss dates, he would post a listing each day tracing the history of some newspaper strip or comic book feature. We engaged in some friendly e-mailed debates about some of his facts but I never questioned Don's devotion to getting things right. I hope his family arranges for someone else to continue the project.