Computer hardware is hot among holiday buyers this season, according to data out yesterday from ComScore.

As online buyers scoop up iPads, e-readers, laptops, and other portable devices, computer hardware is ringing in the holidays as the product category showing the most growth for the season so far, a 25 percent increase compared with last year.

Lower prices on flat-panel TVs is spurring growth in consumer electronics, helping that category grow 22 percent among online buyers over the same period last year, says ComScore. Books and magazines are also proving to be a popular gift item, up 21 percent from last year.

Capping off the online product categories that showed the most growth over last year are computer software (not counting games), which grew 16 percent, and toys, which are up 15 percent.

ComScore's data compares online sales for the first 47 days of the November-December holiday shopping season, which this year covers November 1 to December 17.

Overall, online sales this year have been quite a bit merrier than in 2009. For the season to date, cybershoppers have spent a total of $27.46 billion, according to ComScore, a 12 percent increase over last year. For the week ending December 17, sales hit $5.15 billion, up 14 percent from 2009.

In November, Cyber Monday alone saw $1 billion in sales, said ComScore, a 16 percent gain in sales over the same day last year and the heaviest online spending day in history.

Retail promotions, notably free shipping, have also helped. More than 1,500 online vendors participated in a Free Shipping Day on December 17, leading to sales of $942 million, a 61 percent jump over the corresponding day last year when there was no such promotion.

"Free shipping has certainly become one of the prevalent themes of the 2010 holiday season," ComScore Chairman Gian Fulgoni said in a statement. "Since the week before Thanksgiving, we've seen the majority of online retail transactions use free shipping, which confirms the appeal of the offer for consumers. Free Shipping Day also appears to have driven a sustained late-season response, with free shipping transactions accelerating in importance in 2010 whereas they actually began to decline during the same period in 2009."