The purpose of this research is to assess how digitalized information posted on social media about tourism destinations (TDs) impacts on consumers, with a particular focus on the role of brand familiarity and the source type and content style of online reviews. Two studies were conducted. First, using an online survey-based 2 × 2 × 2 experimental design with a sample of 548 consumers, we examined the interaction effects of review content style, brand familiarity and source of the post on the perceived informativeness and persuasiveness of online reviews about TDs. The findings showed that, when reviews referred to specific features of TDs (brand), firm-generated content (FGC) was more persuasive and informative than user-generated content (UGC) but, in general reviews, UGC was more persuasive and informative than FGC. A second study, using a sample of 136 consumers, assessed: (i) the impact of review content style and destination familiarity on the perceived diagnosticity (credibility and helpfulness) of online reviews; and (ii) the effects of review content style on visual attention paid, and customer engagement, using eye-tracking and electroencephalography. The findings showed that specific reviews are more diagnostic than general reviews, the positive effect of specific reviews on credibility being stronger for familiar destinations.