Recent years have seen the emergence of Web2.0, in which users are not only passive recipients of the featured content, but actively engaged in constructing it. Sites such as "Facebook" and "Myspace" are typical examples of this, as are blogs that allow users to present themselves online, to write about their daily lives or even to establish themselves as an authority on a particular subject. Due to the opportunities for self-reflection and interactive learning offered by blogs, they have also become one of the emerging tools in language pedagogy and higher education. At the same time, peer feedback is a technique that is increasingly used by educators instead of, or in addition to, tutor feedback, due to its potential to develop students' understanding of standards, to initiate peer feedback, and to engage the student in the process of learning and assessment. This paper is concerned with the question to what extent blogs can facilitate peer feedback and what issues need to be addressed for them to be a valuable tool in this process. After reviewing the recent literature on peer feedback and the specific issues emerging from providing feedback through computer mediated communication (CMC) technologies, the paper presents the results from a pedagogic research project in an advanced German language class in which blogs were used for this purpose. Drawing on students' blogs as well as the responses given by students in questionnaires and focus groups and responses by experienced tutors in interviews, the paper argues that blogs are potentially valuable tools for peer feedback, but entail the need to address specific issues regarding the choice of CMC tool for feedback tasks, training in the use of interactive online tools and the roles of teachers and students.