Talk at MIT8, May 3, 2013: Social media platforms have evolved from spaces for personal exchanges to environments for real-time news and information, influencing how media organisations respond to breaking news, how journalists go about their reporting and whose voices are heard. The media logic of emerging communications technologies, where knowledge, expertise and authority are networked and distributed, chafe with existing, hierarchical models of journalism. This presentation will discuss how social media are reconfiguring definitions of journalism and professional constructs of the journalist, as media professionals negotiate a hybrid news ecosystem that blurs the line between the public, the private and the corporate.