In November and December, the number of online transactions increased by 37 percent, and overall sales jumped by 25 percent. But the average ticket size declined by 9 percent, according to Chase Paymentech, which analyzes information across the top 50 e-commerce retailers.

As it turns out, more consumers are turning to e-commerce for more of their everyday spending, rather than reserving online purchases for big-ticket items.

Here are Chase’s three reasons for the decline:

• More consumers are purchasing digital media, which has a lower price point than most physical goods — MP3s cost less than CDs, e-books cost less than paperbacks, and apps cost less than game cartridges.
• Prices for popular electronics, such as tablets, e-readers and TVs, are falling.
• More retailers are offering free shipping, which eliminates the incentive to fill carts to reach a free-shipping threshold.

EBay, which is the first major e-commerce provider to report Q4 results, confirmed it was also seeing the trend. The company’s payments division, PayPal, reported smaller transactions during the fourth quarter across the merchants it serves.

John Donahoe, eBay’s CEO, explained in an interview that the biggest driver of that trend was eBay’s acquisition of Zong, a mobile payments provider that powers the sale of digital goods. In addition, Donahoe said retailers, including eBay, heavily discounted products in order to drive more purchases this holiday.

Amazon, which is the leading e-commerce provider, also said that it is selling a lot of low-priced digital goods, ranging from e-books to MP3s.

Historically, the company has said that Christmas is the largest day of digital sales on Amazon.com, followed by Dec. 26. In 2010, from Christmas Eve through Dec. 30, Amazon customers purchased three times more digital content — including Kindle books, magazines, movies, TV shows, music and digital games — compared to the weekly average for the year.

Despite transactions declining overall, Chase identified two exceptions: Apparel and footwear rose 6 percent; toys rose 10 percent year over year.

(Amazon photo courtesy of thisisbossi)

Although the season kicked off with a bang, there were fears that consumer confidence would fall as the end of the year approached. That did not happen, with people continuing to fill their virtual shopping carts until the very last minute; 10 individual days surpassed $1 billion in spending.

According to comScore, the final tally for online spending for the months of November and December was $37.2 billion, representing a 15 percent increase over last year.

ComScore tracks purchases made on Web sites from a fixed Internet connection, excluding spending done via mobile phones and tablets, so presumably the numbers could be higher.

While the numbers being reported sound positive, some analysts worry if they were enough to give giants like Amazon the growth rates needed to hit expectations. Wall Street analysts are expecting Amazon to post a fourth-quarter growth rate of 38 percent, which would mean it would have to be growing twice as fast as the average market.

But Chase Paymentech’s annual Cyber Holiday Pulse Index painted a rosier picture of the holiday season. Based on tracking 50 of the leading online merchants in the U.S., the report found that during the final two months of the year, transactions were up 37 percent and sales rose 25 percent.

One of the reasons for the huge gains, it said, was because Christmas fell on a Sunday this year, allowing merchants to guarantee shipping much later into the week and giving consumers more time to make online transactions.

To be sure, the increase in online shopping is coming from somewhere — most likely at the expense of traditional retail, which is expected to report a less impressive 4 percent growth rate this year.

“It’s clear that e-commerce continues to gain market share from traditional retail due to the attractiveness of the Internet’s convenience and lower prices,” said comScore Chairman Gian Fulgoni. “Consumers were especially attracted to the deals and discounts available through digital channels -– particularly free shipping, which occurred on well over half of transactions this season.”

The most impressive finding of the season was that 10 individual days surpassed $1 billion in spending, compared to only one day in 2010.

Here is a list of the 10 biggest online shopping days in 2011, led by Cyber Monday:

(Image credit: iStockphoto.com/mbortolino)

But the strategy might backfire. Not only are employees upset that they’ll have to staff the stores instead of being able to stay with their families, the move could cannibalize the retailers’ own online and mobile efforts.

Historically, shoppers have lined up in the early hours on the day after Thanksgiving — which has come to be known as Black Friday — to race into stores and be the first to scoop up discounts ahead of the holidays.

This year, stores are jumping the gun by opening a day earlier. Wal-Mart will open at 10 pm, two hours ahead of last year’s opening; Toys “R” Us will open at 9 pm, an hour earlier than last season; and Target will open for four hours when the clock strikes midnight.

On behalf of employees, Change.org has kicked off a petition, “Tell Target to Save Thanksgiving,” which argues that night openings rob hourly and salary workers of time off with their families.

But there may also be an economic reason to maintain standard practices.

Most of these retailers have major online presences and multiple mobile applications, including on the iPad. If they are open 24 hours a day online, must they actually open the doors, too?

After all, Amazon.com is never considered closed.

To get a sense of the strategy, we talked to someone who works on mobile and online strategy at one of the major retailers that is opening early. He told AllThingsD that he was worried about the impact opening early will have on mobile traffic, since traditionally their peak traffic hits between 3 am and 5 am, before stores open on Black Friday.

If customers have the option of visiting the stores in person earlier, it’s unclear whether that pattern will continue — and whether people will do some extra shopping while killing time standing in line waiting for the doors to open.

Even though mobile is still a small contributor compared to online traffic or store traffic, the retailer in question has scaled its infrastructure to accommodate this early-morning surge.

In general, the 2011 holiday season is expected to drive record sales online and from mobile devices.

Chase Paymentech, which analyzes information from the Top 50 e-commerce retailers, reports that online sales are up 25 percent compared to last year. A separate study by IBM predicts that traffic to retail sites from mobile devices is expected to more than double this month from the last holiday season, reaching 15 percent of all visits to retail sites. Last year, on “Cyber Monday,” mobile visits totaled only 3.9 percent.

But Andrew Lipsman, VP of industry analysis at comScore, said he did not believe the impact of opening early would be very significant.

“Thanksgiving Day and Black Friday are not huge online spending days,” he said. “So, even if sales are relatively soft, it should not have a significant impact on the full season for online retailers. At the end of the day, it will likely be a rounding error — if anything.”

ComScore’s data excludes sales made on tablets or mobile phones, but it estimates that those devices account for a minor amount of e-commerce spending — roughly 3 percent.

Here are the key online shopping dates in 2010:

Target Photo Credit: djLicious.

Black Friday. Cyber Monday. Mobile Tuesday.

What’s next, Debt Consolidation Loan Wednesday? 401(k) Withdrawal Thursday? Pavlov’s Dog Friday?

Try Green Monday. Turns out, the Monday two weeks before Christmas is also a shopping holiday, one apparently held in celebration of the seasonal deadline for free shipping. “This is the last minute [to ship]” said eBay (EBAY) executive Jim Griffith. “It’s do or die.”

Although, given the current economic climate, it’s “do less.” Because according to Chase Paymentech’s Cyber Holiday Pulse Index, the average dollar amount of purchases made on Cyber Monday this year was down 12 percent from last year (click on the charts below). Though there are 14 percent more total transactions this year over last, the typical shopper spent $7.19 less per transaction. “Cyber Monday was very interesting,” said Aaron Press, Director of Market Analysis for Chase Paymentech. “Transaction volume was well ahead of last year for that day, but sales growth was meager. For the entire holiday season, the slower rise in sales volume compared to the steeper increase in transactions has resulted in the average ticket being lower on most days.”

Black Friday. Cyber Monday. Mobile Tuesday.

What’s next, Debt Consolidation Loan Wednesday? 401(k) Withdrawal Thursday? Pavlov’s Dog Friday?

Try Green Monday. Turns out, the Monday two weeks before Christmas is also a shopping holiday, one apparently held in celebration of the seasonal deadline for free shipping. “This is the last minute [to ship]” said eBay (EBAY) executive Jim Griffith. “It’s do or die.”

Although, given the current economic climate, it’s “do less.” Because according to Chase Paymentech’s Cyber Holiday Pulse Index, the average dollar amount of purchases made on Cyber Monday this year was down 12 percent from last year (click on the charts below). Though there are 14 percent more total transactions this year over last, the typical shopper spent $7.19 less per transaction. “Cyber Monday was very interesting,” said Aaron Press, Director of Market Analysis for Chase Paymentech. “Transaction volume was well ahead of last year for that day, but sales growth was meager. For the entire holiday season, the slower rise in sales volume compared to the steeper increase in transactions has resulted in the average ticket being lower on most days.”