11. A non-transitory computer-readable storage medium containing instructions for controlling a computer system of an electronic marketplace to provide data about an item by a method comprising: storing a plurality of queries previously submitted to the computer system of the electronic marketplace, wherein individual previously-submitted queries are stored with a popularity of submission for the previously-submitted query; responsive to a link-selection request by a user for a web page of a media web site provided by a media content server, receiving an automatically generated request from the media content server to provide information based at least in part on web page content to be displayed on the media web site, the media content server being different than the computer system of the electronic marketplace, the web page content submitted in the generated request having been derived by the media content server; matching the content to the item by at least: identifying a previously-submitted query from the plurality of previously-submitted queries as a matching query, said identifying based at least in part on a relevance of the matching query to the web page content and the popularity of submission of the matching query; and selecting the item from a set of one or more items that have been determined to correspond to the matching query; and providing, asynchronously relative to when the web page content is made available by the media content server, the information about the selected item to be displayed on the media web site along with the web page content.
11. A non-transitory computer-readable storage medium containing instructions for controlling a computer system of an electronic marketplace to provide data about an item by a method comprising: storing a plurality of queries previously submitted to the computer system of the electronic marketplace, wherein individual previously-submitted queries are stored with a popularity of submission for the previously-submitted query; responsive to a link-selection request by a user for a web page of a media web site provided by a media content server, receiving an automatically generated request from the media content server to provide information based at least in part on web page content to be displayed on the media web site, the media content server being different than the computer system of the electronic marketplace, the web page content submitted in the generated request having been derived by the media content server; matching the content to the item by at least: identifying a previously-submitted query from the plurality of previously-submitted queries as a matching query, said identifying based at least in part on a relevance of the matching query to the web page content and the popularity of submission of the matching query; and selecting the item from a set of one or more items that have been determined to correspond to the matching query; and providing, asynchronously relative to when the web page content is made available by the media content server, the information about the selected item to be displayed on the media web site along with the web page content. 14. The non-transitory computer-readable storage medium of claim 11 , wherein the identifying of previously-submitted queries includes selecting a particular previously-submitted query that is most popular.