That's the household median. When you combine/compare the data in [1] and [2] that median makes sense when you consider two income households. The individual median is around half that value (fits in the $25,000-27,999 bracket somewhere, assuming a uniform distribution across that range it'd be around $26,500).

[1] http://en.wikipedia.org/wiki/Household_income_in_the_United_...

[2] http://en.wikipedia.org/wiki/Personal_income_in_the_United_S...