Black Friday was the heaviest online spending day to date, according to a new comScore report that says e-commerce sites sold 1.042 billion worth of merchandise on November 23. That’s 26-percent more than what digital consumers shed out last year, the research firm says.

Customer interest spiked on Black Friday, but it only accounted for a fraction of the online spenditure this shopping season.  eShops generated $13.7 billion in revenue in the first 23 days of the November, including $633 million made on Thanksgiving day. That’s a 32 percent increase from 2011.

comScore found that 57.3 million Americans visited online retail sites on Black Friday alone, a number that represents an 18 percent swell in traffic.  Amazon was the most visited destination, followed by WalMart, Best Buy, Target and Apple.

With Black Friday online sales up 26 percent and surpassing $1 billion for the first time, coupled with early reports indicating that Black Friday sales in retail stores were down 1.8 percent, we can now confidently call it a multi-channel marketing phenomenon,” says  comScore chairman Gian Fulgoni.

Meanwhile, Thanksgiving Day – which has historically been a lighter online holiday shopping day – continues to gain steam, growing well ahead of the current pace as more consumers opted to kick off their holiday shopping immediately after the big meal to take advantage of aggressive retailer promotions.

Another firm, ShopperTrak, also dug up some numbers that offer additional perspective on this Fulgoni’s “multi-channel marketing phenomenon”. Its findings were that mall sales dropped by 1.8 percent in spite of a 3.5 percent increase in foot traffic, a statistic that suggests the competition is getting progressively tougher on the web front.

In addition to reiterating that e-commerce is big, comScore’s figures also validate a recent report by ClickFox: the analytics firm predicted a massive increase in online activity this holiday season ahead of the shopping frenzy.