The history of anti-recession efforts is that they are almost always initiated too late to do any good. This chart, based on recession timelines from the National Bureau of Economic Research, shows the enactment of stimulus plans is a fairly accurate indicator that we have hit the bottom of the business cycle, meaning the economy will improve even if the government does nothing.
from the New York Times
My thoughts: The recession began in December 2007. The stimulus will pass in February 2009. Congress doesn't let much slip by them. The economy could potentially start the recovery phase as early as March, April, or May 2009. Too little, too late.