My client would like a surface mounted track light over her bathroom vanity. I wanted certainty that code would allow a fixture rated only for dry locations in a bathroom. I found this article written by Mark Ode, a staff engineering associate at Underwriters Laboratory Inc on the website for the UL Company.
According to Mark, a dry location luminaire must be installed in a location that is not normally subjected to dampness but may be subjected to temporary dampness. With the proper ventilation, above a bathroom vanity fits this qualification. Inside the shower of course, where water can easily splash on a fixture, a fixture must be wet rated.
His article also explains the difference between wet, damp, and dry UL ratings, as well as a few less common ratings for light fixtures.