1. A computer system comprising the following: one or more processors; system memory; one or more computer-readable storage media having stored thereon computer-executable instructions that, when executed by the one or more processors, cause the computing system to perform a method for dynamically tuning search result rankings to control how the search results are presented in a user interface, the method comprising the following: an act of receiving one or more search results, the search results being displayed within a user interface according to each search result's determined ranking, each search result having one or more associated search result attributes; an act of receiving a tuning input at the user interface, the tuning input indicating that a search result ranking model is to be adjusted for one or more specified search result attributes, the search result ranking model determining how each search result is ranked; and an act of dynamically updating the displayed search results as the search result ranking model is tuned for the specified search result attributes, the dynamic updating including at least one of repositioning, adding and removing search results according to the determined ranking for each search result.