Those numbers far exceed the total U.S. commerce and travel spending that is expected to be up 6 to 8 percent and 4 to 5 percent respectively, according to the company's e-commerce research report.

"We believe the secular growth opportunity will continue to support premium P/E (price to earning ratio) multiples versus offline retail/travel peers for the foreseeable future," the report said.

E-commerce sales and online travel bookings are on track to meet, but not significantly beat, expectations, according to the firm. After a strong May, the company said e-commerce sales volume dropped in June, eroding some potential upside surprises.

"We aren't expecting a significant change to the 2005/2006 margin outlook for e-commerce leaders," the report said. Margin pressures from offline encroachment, comparison shopping (e-commerce and travel search), increasing capital investment and higher advertising costs are likely to weigh on 2Q05 operating income growth rates."

The projections arrive at a time when consumer confidence online appears shaky, as reports of phishing and pharming attacks and lost or stolen personal data spread.

However, according to research firm Gartner, one out of three Internet users is buying less online because of security concerns related to data breaches, identity theft and phishing attacks.

The survey of 5,000 U.S. adults said they worry more about thieves getting undetected access to private credit reports private credit reports and other sensitive financial data than defending against phishing attacks.

"We are seeing unprecedented levels in consumer transactions online. Yet businesses cannot rely on the Internet to lower costs and improve marketing efforts indefinitely if consumer trust continues to decline," Avivah Litan, vice president and research director at Gartner, told internetnews.com last month.

The report called international expansion and consolidation "key growth drivers" for the second quarter of 2005. Amazon and eBay are well positioned to generate incremental growth from their existing e-commerce platforms, while Overstock and Priceline should continue to experiment with new product initiatives, the firm said.

Merrill was also bullish on acquisitions by IAC, which bought AskJeeves, and eBay grab of Shopping.com to create new domestic and international revenue opportunities.

Although online business is set to boom, according to the report, the stock outlook was mixed.

This article originally appeared on InternetNews.com.

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