The US has high per-capita income (lower than Norway, but not by much), but that average hides a lot of income disparity. This percolates to other disciplines as well; lots of highly educated people but also a large disinterested population; plenty of artistic talent but also a majority which is not able to fully appreciate aesthetics.
Some level of homogeneity (which is the true form of equality) is perhaps a characteristic of sophisticated future societies.
Add: Among wealthy nations, Norway, Finland, Sweden and Japan sit at the bottom of income disparity indexes. http://en.wikipedia.org/wiki/List_of_countries_by_income_equ....