39. One or more tangible computer readable storage media storing computer-executable instructions for performing a computer process, the computer process comprising: receiving a request from a source to access content of a target Web domain, the request being addressed to a domain address of the target Web domain; retrieving historical relevance data associated with at least one previous request from another source to the target Web domain from a database; identifying at least one interest keyword that is determined to be relevant to the request based on a combination of the domain address of the target Web domain and the historical relevance data, the historical relevance data including one or more context factors collected from the at least one previous request to the target Web domain; transmitting the at least one interest keyword to a server that serves Web content associated with the interest keyword to the source, responsive to the request; and redirecting the source to access advertising content defined by the at least one interest keyword, responsive to the request.
48. The computer readable storage media of claim 39 wherein the database stores a plurality of interest keywords and the identified interest keyword is identified from the plurality of interest keywords.