In a world where à la carte can describe a way to choose online content, it was only a matter of time until an on-demand news syndication service for audio and video, in addition to text and pictures, landed on the menu. This week, Mochila, a service that calls itself a media marketplace, will be introduced in Chicago at Nexpo, an annual newspaper industry conference. Mochila will be a place where newspapers, magazines, Web sites and broadcasters sell content to other publications. Initially, Mochila will only allow the exchange of text and photographs, but it plans to add audio and...