Barry Ritholz recently wrote to ignore the Black Friday hype, especially NRF survey results:
The track records of these surveys are awful. In 2005, the NRF forecast a 22 percent increase in holiday shopping gains for the Thanksgiving weekend. Full holiday retail sales were up just 1 percent. In 2006, it was 18.9 percent sales increase, versus less than 5 percent actual gains. In 2007, a 4 percent gain was actually a 0.4 percent drop. NRF forecasts for 2008 were even worse, 2.2 percent sales gain versus a drop of 6 percent.
But nothing compares to the NRF’s 2009 Holiday Consumer Intentions and Actions Survey for holiday shopping -- it forecast a stunning 43 percent fall versus actual sales, which were up about 3 percent.
He concluded:
Investors who don’t enjoy losing money should ignore the media coverage of these misleading, inaccurate surveys with extreme prejudice.
I would tend to agree. I played around with the seasonality chart function at stockcharts.com and came up with the following for the SPDR Retail ETF (XRT). 
Retailing stocks tend to underperform the market in December. An analysis of the less liquid Market Vectors Retail ETF (RTH), which had a 13 year history compared to XRT's 8 year history, showed that retailing stocks only outperformed SPY 25% of the time in December (though it outperformed 54% of the time in November). I have also seen other studies that indicate that this stock group tends to peak out about US Thanksgiving time.
Bottom line: Beware of the Black Friday and Cyber Monday hype. This may be a case of where you should buy the rumor and sell the news.
Disclaimer: Cam Hui is a portfolio manager at Qwest Investment Fund Management Ltd. (“Qwest”). The opinions and any recommendations expressed in the blog are those of the author and do not reflect the opinions and recommendations of Qwest. Qwest reviews Mr. Hui’s blog to ensure it is connected with Mr. Hui’s obligation to deal fairly, honestly and in good faith with the blog’s readers.”
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