5. A computer-implemented method to generate a results set of images, comprising: receiving an original query from a user to search a plurality of images, each of which is associated with metadata; generating a first results set based on executing the original query relative to metadata associated with each image in said plurality of images; selecting, from the first results set, a specified number of results ranked highest in the first results set; generating a list comprising terms from metadata associated with each result of the specified number of results; for each term in the list, calculating a weight for that term based on ratings that users, excluding users that tagged an image with that term, gave to that term as an assessment of that term's appropriateness to an image; generating an updated query comprising terms that are in the list and that are weighted based on said weights; excluding all terms of the original query from the updated query; after said excluding, generating a second results set based on executing the updated query relative to metadata associated with each image in said plurality of images; and storing the second results set on a non-volatile or volatile computer readable storage medium.
5. A computer-implemented method to generate a results set of images, comprising: receiving an original query from a user to search a plurality of images, each of which is associated with metadata; generating a first results set based on executing the original query relative to metadata associated with each image in said plurality of images; selecting, from the first results set, a specified number of results ranked highest in the first results set; generating a list comprising terms from metadata associated with each result of the specified number of results; for each term in the list, calculating a weight for that term based on ratings that users, excluding users that tagged an image with that term, gave to that term as an assessment of that term's appropriateness to an image; generating an updated query comprising terms that are in the list and that are weighted based on said weights; excluding all terms of the original query from the updated query; after said excluding, generating a second results set based on executing the updated query relative to metadata associated with each image in said plurality of images; and storing the second results set on a non-volatile or volatile computer readable storage medium. 6. The method of claim 5 , wherein the list comprises terms from only tags, including tags that were associated with particular images by users other than users that uploaded the particular images.