16. A system comprising: a user interface for displaying a web document; and a processor in communication with the user interface and coupled to computer-readable storage media containing instructions to be executed by the processor for performing operations including: receiving the web document for display on the user interface; analyzing content of the web document for identifying content for use in generating a plurality queries related to the content of the web document, the analyzing including: parsing the web document into blocks of parsed information including text information, hypertext information, or meta information; selecting candidate phrases from the parsed information; classifying the candidate phrases utilizing a trained machine learning process that employs a binary or multi-class classifier to predict a likelihood that the candidate phrases have a particular class label; and generating, as the plurality of queries, a list of advertising phrases ranked by a classification likelihood; selecting at least one query of the plurality queries utilizing, at least in part, query frequency information, the query frequency information comprising a list of search queries submitted most frequently by users of a search engine based on analysis of at least one of a search engine cache or search engine log files, the selecting comprising comparing the list of search queries from the query frequency information with the plurality of queries from the web document; and displaying one or more advertisements on the user interface in conjunction with display of the content of the web document, the one or more advertisements being automatically determined based upon the at least one of the queries selected, at least in part, utilizing the query frequency information and the analyzing the content of the web document.
16. A system comprising: a user interface for displaying a web document; and a processor in communication with the user interface and coupled to computer-readable storage media containing instructions to be executed by the processor for performing operations including: receiving the web document for display on the user interface; analyzing content of the web document for identifying content for use in generating a plurality queries related to the content of the web document, the analyzing including: parsing the web document into blocks of parsed information including text information, hypertext information, or meta information; selecting candidate phrases from the parsed information; classifying the candidate phrases utilizing a trained machine learning process that employs a binary or multi-class classifier to predict a likelihood that the candidate phrases have a particular class label; and generating, as the plurality of queries, a list of advertising phrases ranked by a classification likelihood; selecting at least one query of the plurality queries utilizing, at least in part, query frequency information, the query frequency information comprising a list of search queries submitted most frequently by users of a search engine based on analysis of at least one of a search engine cache or search engine log files, the selecting comprising comparing the list of search queries from the query frequency information with the plurality of queries from the web document; and displaying one or more advertisements on the user interface in conjunction with display of the content of the web document, the one or more advertisements being automatically determined based upon the at least one of the queries selected, at least in part, utilizing the query frequency information and the analyzing the content of the web document. 17. The system according to claim 16 , the operations further comprising: displaying the at least one of the queries selected on the user interface prior to displaying the one or more advertisements; and displaying the one or more advertisements on the user interface following user selection of the at least one of the queries displayed on the user interface.