A new study from Deloitte (The Shift Index) talks about the increase in competitiveness of the U.S. economy over the past 30-40 years. Alex Tabarrok has a very good summary of the piece along with two graphs from the paper. It is your must read post of the day.
Deloitte also released a version in the Harvard Business Review, available here as a pdf. I'll say more after I get a chance to read it. Also, if you need to know what the Herfindal-Hirschman Index (HHI) is just see Wikipedia or Investopedia.