Americans long ago adopted the notion of the “holiday season,” extending what were originally one-day celebrations into weeks of merriment and cheer. So it should come as little surprise that they’re starting to drag out Cyber Monday, too.

E-commerce experienced its first back-to-back-to-back billion-dollar shopping days on Nov. 28-30. (David Paul Morris/BLOOMBERG)

“Cyber Monday kicked the week off with a bang as consumers opened their wallets to the tune of $1.25 billion, but it was only the beginning of a very strong week of online holiday spending,” comScore Chairman Gian Fulgoni said in a statement. “As the deals from this week expire, it will be important to see the degree to which consumers return to the same retailers to continue their holiday shopping.”

Not to worry, though, because the trend doesn’t appear pinned down to a single “Cyber Week.” Rather, online spending for the first 32 days of the November-December holiday season totaled $18.7 billion, also marking a 15 percent increase over the same period last year as more Americans turn to the Internet for their shopping needs.

So what’s luring them online? According to the comScore data, more than one-third of shoppers consider free shipping “very important” and would not make a purchase without it, while another 42 percent say that free shipping is “somewhat important” and that they actively seek out free shipping deals. Coincidently enough, the report shows that more than half of all transactions this holiday season have included free shipping, with the week of Cyber Monday seeing a nearly 10 percent increase in free shipping deals over the same week in 2010.

Ah, the power of listening to your customers.

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