All the single ladies...and men.
If you have yet to "put a ring on it" and want to know the spatial extent of others flying solo, check out today's maps. Spatial analysis tools are used to efficiently and precisely locate many a sought-after item: real estate, eateries, travel routes, careers, and now (with the help of the US Census Buereas American Community Survey): a mate (or just a date, depending on what you're in the market for).
The maps below from The Boston Globe and Pharyngula's Science Blog outline approximate number of single males and females in the United States surrounding major metro areas. Based on these projections, it seems as though Southern California is home to more single men, while the Northeastern United States has more single women. If you are a (hetero-normative) man in SoCal or a (hetero-normative) woman in DC and found your mate (or date) with ease...consider yourself an expert. Or just awesome. If you are on the look out, consult these analyses before you make your next (literal) move!
If you happen to be in the Washington, DC metro area and would like additional perspectives, check out Tyler Cowen's, "A simple theory of being male in Washington" or the Washington Post's analysis on why DC's single ladies are the happiest in the nation.