The Informedia group at Carnegie Mellon University has since 1994 been developing and evaluating surrogates, summary interfaces, and visualizations for accessing digital video collections containing thousands of documents, millions of shots, and terabytes of data. This paper surveys the Informedia user studies that have taken place through the years, reporting on how these studies can provide a user pull complementing the technology push as automated video processing advances. The merits of discount usability techniques for iterative improvement and evaluation are presented, as well as the structure of formal empirical investigations with end users that have ecological validity while addressing the human computer interaction metrics of efficiency, effectiveness, and satisfaction. The difficulties in evaluating video summarization and browsing interfaces are discussed. Lessons learned from Informedia user studies are reported with respect to video summarization and browsing, ranging from the simplest portrayal of a single thumbnail to represent video stories, to collections of thumbnails in storyboards, to playable video skims, to video collages with multiple synchronized information perspectives.