Courtesy of Richard Florida, a map of American singles populations with pretty clear implications for anyone seeking a date. In essence, Eastern cities (and especially the NY-DC corridor) have a lot more single women than men, and Western cities (especially in California) have a lot more single men than women. (Florida offers his thoughts on why this is here.)
It can't help but put me in mind of a line from the (criminally underappreciated) Kiss Kiss Bang Bang, when Robert Downey Jr. observes that "It's literally like someone took America by the East Coast and shook it, and all the normal girls managed to hang on"--except that it was evidently not just the normal ones.
(via Patrick, filling in for Andrew)