21. A system comprising: at least one computing device providing: an ad control system that receives a request associated with an initial web object, the request being for at least one advertisement, each advertisement comprising content that is to be served for display with the initial web object; an ad control subsystem that selects one or more keyword candidates from the initial web object; a query subsystem that instructs an Internet search engine to identify via query web pages that include the one or more keyword candidates, the query being performed using the one or more keyword candidates; an analysis subsystem that analyzes the results of the query, and selects one of the keyword candidates as a representative keyword based on a contextual relevancy of each of the one or more keyword candidates to the initial web object, the contextual relevancy of each of the one or more keyword candidates being identified using the web pages that include the one or more keyword candidates identified by the query subsystem; and an ad instruction subsystem that instructs an ad engine to select one or more advertisements based on the representative keyword selected using the contextual relevancy of each of the one or more keyword candidates to the initial page, and instructs an ad server to serve the one or more advertisements with the initial web object in response to the request.
21. A system comprising: at least one computing device providing: an ad control system that receives a request associated with an initial web object, the request being for at least one advertisement, each advertisement comprising content that is to be served for display with the initial web object; an ad control subsystem that selects one or more keyword candidates from the initial web object; a query subsystem that instructs an Internet search engine to identify via query web pages that include the one or more keyword candidates, the query being performed using the one or more keyword candidates; an analysis subsystem that analyzes the results of the query, and selects one of the keyword candidates as a representative keyword based on a contextual relevancy of each of the one or more keyword candidates to the initial web object, the contextual relevancy of each of the one or more keyword candidates being identified using the web pages that include the one or more keyword candidates identified by the query subsystem; and an ad instruction subsystem that instructs an ad engine to select one or more advertisements based on the representative keyword selected using the contextual relevancy of each of the one or more keyword candidates to the initial page, and instructs an ad server to serve the one or more advertisements with the initial web object in response to the request. 23. The system of claim 21 wherein the initial web object is a media object.