1. A computer-implemented method for responding to a search query from a user, the method comprising: receiving a search query from a requesting computer user, the search query being directed to a query topic; obtaining a set of search results responsive to the search query; and determining whether the requesting computer has an interest circle corresponding to the query topic and, upon determining the condition that the requesting computer user does not have an interest circle corresponding to the query topic: identifying a plurality of computer users, each of the plurality of computer users having an established interest circle corresponding to the query topic, wherein identifying the plurality of computer users comprises identifying the plurality of computer users irrespective of any user-established relationship with the requesting computer user; ordering the set of search results according to the interest circles of the identified plurality of computer users; and returning higher ordered search results to the requesting computer user.