How Bad is Inequality in America?

Matt Yglesias:

How much economic inequality is there in the United States? So much that Lloyd Blankfein, the CEO of Goldman Sachs, went on television this morning and warned that it's "destabilizing" and making it impossible for the political system to "deal with problems." Even Blankfein thinks "Too much of the GDP over the last generation has gone to too few of the people."

As this notion spreads through the intellectual class, will it eventually lead to policy changes or just lots of nodding and tsking?