Call for Papers: Special issue of the Journal of Computer-Mediated Communication, "Communication Approaches to Participatory Websites and User-Generated Content." Joseph B. Walther, guest editor. Among the most important developments in CMC are participatory websites featuring user-generated content (e.g., Web 2.0 sites with product/seller reviews, social network sites that invite "friends'" contributions, talk-back features on online news sites, wikis, etc.). This issue of JCMC will focus on the extension, adaptation, and application of theoretical approaches to the uses and effects of these messaging systems. We invite evidence-based papers that address the creation and impacts of user-generated content, system-aggregated indicators of user input, and/or their interplay with owner-generated content, on the perceptions, attitudes, and behavior of participants and viewers of such sites. Criteria for acceptance will involve the degree of exemplification of the communication aspects of the topic, and the degree to which articles join theoretical analysis with rigorous empirical investigation. Manuscripts will be reviewed anonymously by a special editorial board and other JCMC reviewers; authors must prepare submissions to facilitate anonymous review. Submissions must not exceed 30 pages, and must reflect APA (6th ed.) style. Deadline for submission is December 10, 2011. Please contact the editor with any questions, or to submit manuscripts as attachments, at <mailto:jcmc@cmcresearch.org> jcmc@cmcresearch.org. === Joseph B. Walther Professor of Communication Professor of Telecommunication, Information Studies & Media Michigan State University https://www.msu.edu/~jwalther/