Tim Keller cites a book by David Brooks named 'Bobos in paradise':
Over last hundred years there was always a cultural war between the bourgeois and the bohemians.
Now we have a hybrid of the two: 'bobos'. They have the moral relativism of the bohemians with the materialism of the bourgeois.
Tim Keller suggest urbanised Christians need to be the opposite type of hybrid: love of diversity of teh bohemians with the moral seriousness of the bourgeois.
Perhaps they could be called 'obobs' he says...