Even though a recession is commonly defined as two consecutive quarters of decrease in the GDP , it is now "official" that we've been in a recession since December 2007... even though GDP hasn't decreased for two consecutive quarters yet.

http://money.cnn.com/2008/12/01/news/economy/recession/index.htm

The National Bureau of Economic Research said Monday that the U.S. has been in a recession since December 2007, making official what most Americans have already believed about the state of the economy...

"The committee views the payroll employment measure, which is based on a large survey of employers, as the most reliable comprehensive estimate of employment," said the group's statement. "This series reached a peak in December 2007 and has declined every month since then."

And from the National Bureau of Economic Research itself: http://wwwdev.nber.org/dec2008.html

The committee determined that the decline in economic activity in 2008 met the standard for a recession, as set forth in the second paragraph of this document. All evidence other than the ambiguous movements of the quarterly product-side measure of domestic production confirmed that conclusion.

It seems to me that there really isn't any hard and fast rule as to what constitutes a recession anymore--it's an ambiguous event that begins when some arbitrary group of people subjectively decides that it happens. Apparently, since we were a year into what these people wanted to call a recession but we had "ambiguous" movements in the GDP that wouldn't technically qualify as a recession, they just declared a recession based on other factors--even though those factors really aren't what traditionally define a recession. So I guess we just redefine the terms so we can call it a recession now.

The media is certainly happy to see this. They've been predicting a recession for, what, two years now? Finally, according to this declaration, they've been vindicated. I guess if you predict something long enough you will eventually be right. Especially if you redefine the terms.

EDIT: Two days after I posted this comment, I stumbled upon this commentary that really highlights the arbitrary (and somewhat suspicious) declaration of a recession as of December 2007. Definitely read this link!