19. A computer program product comprising a non-transitory computer readable medium storing computer instructions for adaptive indexing of multimedia content, the computer instructions comprising: instructions for identifying a keyword associated with a first feature and a second feature found in a data portion of a multimedia item, the feature being of a first media type and the second feature being of a second media type, and the first media type being associated with a first weight and the second media type associated with a second weight; instructions for determining a relevance for the keyword by calculating a relevance value using said first weight and said second weight; instructions for updating the first weight associated with the first media type based on a search result selected by a user from a set of search results that were identified to the user in response to a query from the user to produce an updated first weight, wherein the selected search result indicates a multimedia item having a feature being of the first media type and another feature being of the second media type, each of the features being associated with the keyword; instructions for updating the second weight based on a particular set of content items being identified by the selected search result to produce an updated second weight; and instructions for updating the relevance of the keyword using the updated first weight, and the updated second weight.
19. A computer program product comprising a non-transitory computer readable medium storing computer instructions for adaptive indexing of multimedia content, the computer instructions comprising: instructions for identifying a keyword associated with a first feature and a second feature found in a data portion of a multimedia item, the feature being of a first media type and the second feature being of a second media type, and the first media type being associated with a first weight and the second media type associated with a second weight; instructions for determining a relevance for the keyword by calculating a relevance value using said first weight and said second weight; instructions for updating the first weight associated with the first media type based on a search result selected by a user from a set of search results that were identified to the user in response to a query from the user to produce an updated first weight, wherein the selected search result indicates a multimedia item having a feature being of the first media type and another feature being of the second media type, each of the features being associated with the keyword; instructions for updating the second weight based on a particular set of content items being identified by the selected search result to produce an updated second weight; and instructions for updating the relevance of the keyword using the updated first weight, and the updated second weight. 24. The computer program product claim 19 , wherein the instructions for updating the first weight comprise instructions for updating the first weight based on a distribution of determined feature types across N queries, where N>1.