Jon Meacham is leaving the co-anchor’s chair at Need to Know, and Alison Stewart will be the solo host, according to MediaBistro’s TV Newser blog. Meacham is staying on with producing station WNET to lead a new series, Perspectives, to air on TV and online. “I love Alison and the Need to Know team, but I don’t think the broadcast needs me as a co-anchor,” Meacham said.