1. A computer-implemented method of determining visual similarity, comprising: receiving an image including an item of interest to a user; identifying the item of interest contained in the image; determining a plurality of similar items based at least in part upon a type of the item of interest; determining a set of item descriptors for at least a portion of the plurality of similar items, each item descriptor providing a score indicating a relatedness of a visual aspect between the item of interest and a respective one of the similar items; determining a user type, corresponding to the user, at least in part by monitoring an online search history of the user and comparing the online search history of the user with online search histories from a plurality of customers; obtaining user-generated visual similarity data for the type of the item of interest, the user-generated visual similarity data indicating a subjective weighting to be applied to each of the item descriptors based at least in part upon data obtained from a plurality of customers of the type of item and based at least in part upon weighting preferences of the type of the user; determining, using at least one device processor, a visual similarity score for each of the portion of similar items by applying the subjective weightings to values of the items descriptor values for the similar items; and selecting, using the at least one device processor, a determined number of the similar items to be provided to the user as visually similar items based at least in part upon the visual similarity scores for the similar items, wherein the user-generated visual similarity data is obtained by monitoring customer interactions with the item of interest and the similar items, and by monitoring the browsing behavior of the user.