"Growth is down slightly from last year, but you have to understand that any new medium loses steam after its initial peak," said Dan Hess, senior vice president at comScore. "We're still really positive about this year's growth, given the current economy and the mixed messages that consumers are sending."
The forecast, which excludes all travel spending, also expects total quarterly spending to go beyond the $20 billion threshold for the first time.
The sales of jewelry and watches are estimated to grow by more than $739 million, compared to last year. At 67 percent, that make them the fastest-growing products available online. Sales of furniture and appliances are expected grow by 58 percent, and computer software sales are projected to increase by 43 percent.
"Pure online sales is only half of the story this year," said Hess. "I see the blurring of the lines between channels as the real story: consumers buying online, and then picking up the products at stores; consumers getting their information about a product online, and then purchasing it at a store; etc."