The practice of watching TV while using a secondary device is becoming a widespread social phenomenon. At the same time, a growing amount of studies, focus on users’ communicative behaviors while consuming specific TV programs or genres. Despite a diffuse scholarly interest on this issue, few studies compare different forms of online audience participation generated around different TV genres. This paper presents a full-season comparative study of live tweeting practices generated around a political talk show and a talent show. We focused on the following research questions: RQ1. What triggers active audience engagement in the two formats? RQ2. Do people tend to delegate or cover up the expression of opinion when the show deals with politics rather than entertainment? To answer these questions, from August 30 2012 to June 30 2013, we collected all tweets containing either the official hashtag of the political talk show Servizio Pubblico or the sixth Italian edition of X-Factor for a total amount of about 1 million tweets. For each episode (37), we identified peaks of Twitter engagement and observed the corresponding TV scene. We found that surprise and suspense play a different role in enacting online audience engagement. Further content analysis on a sample of eight peaks (13,189 coded tweets) confirmed the substantial difference in the way opinions are expressed when commenting on politics and entertainment.