The present article studies the concept of advertising value in marketer-generated content (MGC) on social network sites (SNSs) fan pages. The study goes beyond investigations of vehicle effects on consumer perceptions of valuable advertising. By extending the advertising value framework towards the media, the role of perceived enjoyment and credibility on a SNS is tested to determine the value of MGC, and its impact on electronic word of mouth (eWOM) and website visit intention leading to purchase intention. The hypotheses are tested by means of a survey of 395 followers of a popular retailer’s real Facebook fan page. A partial least squares regression of the variables supports the influence of enjoyment and credibility on the value of MGC, which leads to behavioural responses. The results contribute to the understanding of advertising value creation on SNSs based on media antecedents and provide practical insights into social media advertising strategies.