comScore, Inc. released the first in a series of twice weekly holiday season e-commerce updates, revealing that the first 18 days of the holiday season saw more than $7 billion in online retail spending, a 17-percent gain versus the corresponding days last year.

"The online holiday shopping season got off to a slow start in the first week of November, but it has since picked up sharply," said comScore Chairman Gian Fulgoni. "Sales in the first ten days of November were up modestly versus year ago, but surged to levels in excess of 20 percent by mid-November.

It's likely that warmer than average weather at the beginning of November kept people outdoors and away from their computers, weighing down early holiday season sales, especially for key online categories like apparel. The growth rates during the second and third weeks of November are likely to be better indicators of how the remainder of the season will play out."