30. The method as in claim 29, wherein the second search query comprises multiple search terms, and step (g) comprises using the correlation data to identify terms that are related to each of the miltiple search terms.
29. The method as in claim 1, further comprising the steps of: (f) receiving a second search query from a second user; (g) using at least the second search query and the correlation data to identify a set of related search terms; and (h) presenting the set of related search terms to the second user, in conjunction with search results, as suggested refinements to the second search query.