This article addresses the issue of social media from the perspective of prosumption. The term social media has recently replaced the descriptive discourse on new media and communication technologies. This change implies that, from among the various uses of new media and communication technologies, one use has prevailed. There is no consensus about the exact meaning of the term social media and several scholars still prefer the descriptive approach. The concept of prosumption, which claims that with the rise of digital technologies the barriers separating production from consumption have disappeared, might explain the distinctiveness of social media. This article explores this idea and expectations about the social potential of merging production and consumption in social media by focusing on the issue of audience participation. First, it traces various understandings of agency and subjectivity in the historical conceptions of the audience within media and communication studies. Second, it argues for a conceptual approach to the issues of agency and subjectivity. It proposes the concept of the dispositive as that which simultaneously addresses historical and conceptual issues, presents its implications for the interpretation of social media, and argues for the suitability of the theory of the dispositive for conceptualizing the social potentials of social media.