Multichannel Merchant--RESTON, Va., Nov. 28, 2012 /PRNewswire/ -- comScore (NASDAQ : SCOR), a leader in measuring the digital world, today reported holiday season U.S. retail e-commerce spending for the first 26 days of the November-December 2012 holiday season. For the holiday season-to-date, $16.4 billion has been spent online, marking a 16-percent increase versus the corresponding days last year. Cyber Monday reached $1.465 billion in online spending, up 17 percent versus year ago, representing the heaviest online spending day in history and the second day this season (in addition to Black Friday) to surpass $1 billion in sales.