In this paper we examine user queries with respect to diversity: providing a mix of results across different interpretations. Using two query log analysis techniques (click entropy and reformulated queries), 14.9 million queries from the Microsoft Live Search log were analysed. We found that a broad range of query types may benefit from diversification. Additionally, although there is a correlation between word ambiguity and the need for diversity, the range of results users may wish to see for an ambiguous query stretches well beyond traditional notions of word sense. Categories and Subject Descriptors H.3.3 [Information Search and Retrieval]: Systems and Software --- performance evaluation. General Terms Measurement, Experimentation. Keywords Diversity, ambiguity.