Viewpoint: Journals for Certification, Conferences for Rapid   Dissemination
  The publication culture in Computer Science is different from that of all other disciplines. Whereas other disciplines focus on journal publication, the standard practice in CS has been to publish in a conference and then (sometimes) publish a journal version of the conference paper. We discuss the role of journal publication in CS.   Indeed, it is through publication in selective, leading conferences that the quality of CS research is typically assessed. 
Joseph Y. Halpern and David C. Parkes
cs.DL