Source: Wonkblog - (T)he percentage of the labor force that had been unemployed for five weeks or less didn't grow all that much during the economic meltdown.
What changed was what happened after or within those five weeks. In 2007, they typically ended with a job. In 2009 and 2010, they more often ended with another few weeks of unemployment. The result is that if you break down the unemployment rate by duration, the problem appears to be almost entirely about long-term unemployment