Flickr photo via brownpau

Is the big snowstorm that blanketed parts of the East coast producing a sales bump for Amazon.com and other online retailers? Web data firm Coremetrics reports online retail sales on Friday through Sunday — the weekend before Christmas, when online sales traditionally drop off — were up more than 20 percent from the same period a year ago. Coremetrics said free shipping and other promotions being dangled by web retailers are luring more shoppers, including those who were snowed in and couldn't get to the malls.

Coremetrics' chief strategy officer John Squire writes:

When you combine the special promotions with guaranteed delivery dates, up-to-date inventory information (a critical consideration for many people this season), and the ability to shop from the comfort and warmth of your own home, it’s easy to see why online shopping is proving compelling to consumers this season. Plus, the last-minute shoppers on the East Coast who had intended to hit the malls this weekend really had no option but to shop online.

Amazon and other web retailers have extended shipping deadlines to capture the late shoppers.

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