When users interact with a search engine their queries reveal three different underlying intents, namely navigational, informational, and transactional. By providing more accurate results depending on such query intents the performance of search engines can be greatly improved. Therefore, query classification has been an active research topic for the last years. However, while query topic classification has deserved a specific bakeoff (i.e. KDD Cup 2005), no evaluation campaign has been devoted to the study of automatic query intent detection. In this paper we review the available query intent detection techniques, we propose an evaluation method and, we use it to compare those methods in order to shed light to their relative performance and drawbacks. In addition to this, we propose future lines of work in both query intent detection and its evaluation.