WSJ piece debunks a bunch of well-oiled myths, among them the origins of Black Friday:

The notion of "Black Friday" originated with the Philadelphia police in the 1960s, who used it to describe the heavy traffic in the city as consumers hit the stores after Thanksgiving, says Nancy Koehn, a retail historian at Harvard Business School. Looking to put a positive spin, retailers started saying it was the day they would turn a profit. "It's one of those apocryphal things that sound great but aren't true," says Ms. Koehn.

As for all those holiday forecasts, they're typically based on surveys taken weeks ago and are frequently wrong.

Last holiday season, most economists released their sales predictions in early September, before the Lehman Brothers bankruptcy and stock-market collapse, which caused an abrupt falloff in consumer spending. "Everything happened after we published our forecast," says Rosalind Wells, chief economist at the National Retail Federation, which forecast a 2.2% rise in holiday sales last year. Ultimately, the NRF reported that sales for the season fell 3.4%.

The Journal found that holiday predictions tend to be too optimistic. Last year, of course, even the most pessimistic were on the high side.