The fact that the Youngers are black now seems less like an innovation than a detail, though it's marvelous to see how precisely Ms. Hansberry caught the tone of black life in the 1950s.
In the first act of "Clybourne Park, " set in 1959, we meet Bev and Russ (Christina Kirk and Frank Wood), who are selling their house to the Youngers (who are talked about but never seen).
As you probably know by now, Mr. Norris's play is a variation on "A Raisin in the Sun, " Lorraine Hansberry's 1959 play about the Youngers, a black family that moves to a white neighborhood in Chicago.