A more useful paradigm: the "Walled World"?

Everybody struggles to group various nations into socioeconomic chunks. We speak awkwardly about the "third world" and the "industrialized world." We even speak euphemistically about the "industrializing world" regardless of whether some countries are actually making progress toward industrialization. This graphic, created by Td Architects in Holland, shows something they call the "Walled World" -- the countries where 14% of the world's population generates 73% of the income -- so much relative wealth that they need to wall off or patrol their borders to block mass migrations. Instead of old labels, should we use "inside" or "outside" the "walled world"? (Click on the image for the big version.)