In this paper, we describe an application, PubCloud that uses tag clouds for the summarization of results from queries over the PubMed database of biomedical literature. PubCloud responds to queries of this database with tag clouds generated from words extracted from the abstracts returned by the query. The results of a user study comparing the PubCloud tag-cloud summarization of query results with the standard result list provided by PubMed indicated that the tag cloud interface is advantageous in presenting descriptive information and in reducing user frustration but that it is less effective at the task of enabling users to discover relations between concepts.