Say what you want about government bailouts, GDP forecasts, credit default swaps, etc. As far as I’m concerned, the true sign we’re in a recession is this: e-commerce spending has dropped for the first time ever.

comScore has somehow figured out that only US$8.2-billion has been spent in online spending this holiday season so far, about a 4% dip from last year’s US$8.5-billion. Assuming comScore is correct – hey, with all forecasts, who really knows for sure – this marks the first time e-commerce is slowing down.

According to the New York Times’ Brad Stone:

“We thought that things would solidify in November,” said Gian Fulgoni, chairman of comScore, who said gut-wrenching declines in the stock market and the auto industry crisis “spooked people who might have been thinking the worst was behind us.”

ComScore will also release its annual prediction for the entire holiday season on Tuesday, after some internal wrangling over whether to hold back the number because of too many unknown factors this year. The data firm is predicting that the overall holiday shopping season will improve slightly in December and end up at the same level as last year. In November and December 2007, the e-commerce market grew by 19 percent from the previous year.

Given that online shopping is arguably a more effective retail experience for customers, this is pretty huge. As I alluded to earlier, this is truly the harbinger of worse things to come. Be afraid, be very afraid.