Research productivity indicators tend to ignore online and social media writing of academics, nevertheless, many academics for instance tweet and blog. It thus seems that there is additional value for writing in these genres. This study sets out to explore what roles writing in these hybrid online genres plays in relation to academics’ research activities. Drawing on in-depth research interviews with 29 academics with various L1s from three different disciplines, the study focuses on the participants’ perceptions of tweeting and blogging, and how they value writing in these genres in relation to core research-writing genres in their fields. Besides some differences in the evaluations between the disciplines, in general the academics expressed a strong orientation towards evaluative regimes related to writing in their core genres, particularly institutional merit systems and peer review systems. At the same time, the hybrid genres seemed to gain value beyond these systems in providing opportunities for self-actualisation and communicating on one’s own terms. The findings provide important insights into the ecology of genres academics make use of in the process of knowledge production.