[WASHINGTON POST]  CENSUS SHOWS INCOMES RISING, MARRIAGES DECLINING FOR BLACKS IN PRINCE GEORGE'S The days of the suburban home (husband, wife and two kids) may be over for a large portion of Prince George’s county residents.  The changing demographics experienced here can be seen among African Americans across the nation.  In 2008, about half of the black households in the county made incomes of more than $75,000 a year, more