http://www.physorg.com/news78679968.html
The real question is whether the preference for light brown is culturally related or part of innate human evolutionary psychology. Two points regarding the first possibility. Before the 19th century, white was considered high status because it meant that the person did not have to work in the field. By the 20th century dark tan was high status because now it meant that the person could afford the leisure of suntanning and wasn"t working in an office 365/24/7. Second issue is methodological: the item here does not report whether (although one assumes) the study was undertaken in the U.S. alone. Perhaps in the Middle East or Africa "white" is preferable? (Just as for Swedes, "exotic" brunette is preferable because almost everyone is blonde!)
On the other hand, this light brown "tan" preference might be "inherent" in our species for reasons that need to be investigated. Just as research has shown there to be an "ideal" female body size/shape (across cultures) for evolutionary reasons (fertility), so too skin coloration might have "mating" ramifications.
It"s too bad that this study focused on the trivial "marketing" aspects of skin color and not the larger questions.