6. One or more machine-readable hardware storage devices storing instructions that are executable by one or more processing devices to perform operations comprising: obtaining search results responsive to a search query submitted by a user; determining, based on usage of a social network by the user, a maturity score for the user, where the maturity score represents a measure of user development of the user within the social network; for a particular type of content associated with a search result, retrieving, from a set of utility score instructions, a utility score instruction for the particular type of content; wherein the utility score instruction defines, for the particular type of content in the social network, a relationship between a utility score and the maturity score; and wherein the utility score represents a measure of utility of the particular type of content to the user as defined by the measure of user development in the social network; and wherein the utility score is determined independent of user input; wherein defined relationships across the set of utility score instructions promote a first pre-defined type of content among less mature users of the social network relative to other maturities of other users of the social network and promote a second pre-defined type of content among more mature users of the social network relative to the other maturities of the other users of the social network; determining, based on the set of utility score instructions and the maturity score, utility scores for the search results; and adjusting rankings of the search results based on the utility scores.
6. One or more machine-readable hardware storage devices storing instructions that are executable by one or more processing devices to perform operations comprising: obtaining search results responsive to a search query submitted by a user; determining, based on usage of a social network by the user, a maturity score for the user, where the maturity score represents a measure of user development of the user within the social network; for a particular type of content associated with a search result, retrieving, from a set of utility score instructions, a utility score instruction for the particular type of content; wherein the utility score instruction defines, for the particular type of content in the social network, a relationship between a utility score and the maturity score; and wherein the utility score represents a measure of utility of the particular type of content to the user as defined by the measure of user development in the social network; and wherein the utility score is determined independent of user input; wherein defined relationships across the set of utility score instructions promote a first pre-defined type of content among less mature users of the social network relative to other maturities of other users of the social network and promote a second pre-defined type of content among more mature users of the social network relative to the other maturities of the other users of the social network; determining, based on the set of utility score instructions and the maturity score, utility scores for the search results; and adjusting rankings of the search results based on the utility scores. 10. The one or more machine-readable hardware storage devices of claim 6 , wherein the user comprises a first user, the maturity score comprises a first maturity score, the utility scores comprise first utility scores, and wherein the method further comprises: determining a second maturity score for a second user requesting the search query; determining, based on the second maturity score, second utility scores for the search results; and adjusting the rankings of the search results based on the second utility scores; wherein the adjusted rankings of the search results based on the second utility scores vary from the adjusted rankings of the search results based on the first utility scores.