Craigslist.com founder Craig Newmark was at the Chronicle yesterday (April 18), where he was quizzed by reporters and others, and said that he feels that while he likes citizen journalism, there’s no substitute for professional writing, professional editing or professional fact checking. How does he feel when he is told that his site is killing newspapers by taking their classified ads? “I don’t take it too seriously.” But he said the accusation has caused him to talk to industry experts to find out more about what’s going on. “Maybe the biggest effect of all is newspaper chains (demanding) high profit margins,” he said. The Chronicle has posted a summary of his remarks and has a pod-cast recording of what he said. [Newmark blogs on sfgate.com]