For the U.S. e-commerce industry, last week was one for the record books. Online holiday shoppers spent $5.499 billion from December 13 to December 19, according digital trends tracking firm comScore.

Spending growth has remained strong right through the final shopping weekend of the holiday season, said comScore chairman Gian Fulgoni.

Last week's tally beat the same week's sales in 2009 by 14 percent at $4.803 billion.

In the final weekend of shopping, online denizens spent $900 million, up 17 percent from the same period in 2009.

The growth rate of 17 percent witnessed during the final weekend capped off the heaviest online spending week of all time at $5.5 billion, Fulgoni said.

So far this holiday shopping season - as measured from November 1 to December 19 - online shopping has reached $28.36 billion as of the latest week, the tracking company said.

Although there are still nearly two weeks remaining before the end of the year, holiday spending is inching very close to the total for the entire 2009 holiday season, a sign of just how much the online retail landscape has improved in the past year.

On Cyber Monday in November, mobile online shoppers set new records.