1. A computer-implemented method of facilitating the navigation of recommended items, the method comprising: receiving, from a recommendation engine, an indication of a plurality of items selected by the recommendation engine to recommend to a user, said plurality of items selected by the recommendation engine based on information reflecting preferences of the user, each of the plurality of items being pre-assigned to at least one item category of a hierarchical browse structure; determining, based on said pre-assigned categorizations, an initial set of item categories associated with the plurality of items, each of the item categories in the initial set being associated with one or more of the plurality of items; selectively filtering out item categories from the initial set of item categories based at least in part on the degree to which particular item categories in the set overlap with other item categories in the set, to thereby create a subset of item categories to present to the user; and providing, based on the created subset of item categories, a recommendations user interface that includes functionality for the user to navigate at least a portion of the plurality of items using the subset of item categories; said method performed in its entirely by a computer system that comprises one or more computers.