The next speakers in our ECREA 2012 panel are Laura Ahva and Maria Hellman, whose interest is in the citizen eyewitnessing of crises. Witnessing has always been a central task of crisis journalism, but citizen-generated content is now increasingly important; citizen eyewitness images are especially central now, and are mediated from the sites of crises to the global audience. The Arab Spring provides a very useful recent example for this.

Professional media and citizen eyewitnessing have become co-dependent on each other, leading perhaps even to a symbiotic relationship or congruence between the two. Audiences use such content to make sense …

The second ECREA 2012 keynote speaker this morning is Clemencia Rodríguez, who will be shifting our focus further towards citizens' media. She notes that it is important to take historical precedents seriously – reacting against the popular representation of recent political unrest as driven and determined by social media, and as leaderless revolutions.

But media have always played a role as mediators, of course – in political communication, social actors negotiate their identities through interaction; media effects theory has this wrong. The visibility of today's ICTs has led to a resurgence of media effects theory, and this needs to be …

The first AoIR 2012 session this Saturday starts with my paper with my colleagues Tim Highfield and Stephen Harrington, which presents our work on the Australian Twitter New Index (ATNIX). Below are the slides – for more, also see my column at The Conversation. Audio to follow soon! I've added the audio now, too.

Sharing the News: Dissemination of Links to Australian News Sites on Twitter from Axel Bruns

Up next at AoIR 2012 is Zizi Papacharissi, whose focus is on structures of affect and their connection to political engagement. What is the texture of feeling here – for example in the expression of sentiment on Twitter? In her talk here, Zizi will focus on the #egypt hashtag.

Twitter is a form of news storytelling here, presenting collectively prodused newsfeeds which interact with the wider news economy; it can be an alternative or a primary channel for information. As a news reporting mechanism, Twitter can also offer premediation for news events which have not yet happened, or act …