It's not just the growing number of people surfing the web or the time they're spending online, but the money they're spending and the way in which they're doing it that is good news for e-commerce merchants.

For example, Nielsen//NetRatings is reporting across the board increases in user metrics such as sessions per person per month; domains and pages visited per person per month; and page views per surfing session.

In simple terms, consumers are looking at a greater number of websites; drilling deeper into them to more thoroughly view their content and then clicking on more links to other websites – which increases the chances that one of those sites may be yours.

They're not just looking however; they're also buying.

According to Alex Burmaster, a European Internet analyst for Nielsen Online, online shopping has risen by 40 percent in the past two years, going from roughly 627 million customers (one in ten of the world's population) to 875 million.

Burmaster also claims that more than 85 percent of Internet users have shopped online; with half of all users having made an online purchase within the past month.

An interesting and ironic statistic is that books are the most purchased item online, accounting for 41 percent of recent sales: interesting because these sales are often made to developing countries such as Brazil, China, Egypt and Vietnam; ironic, because when the Internet debuted, many critics proclaimed it to be the end of print publishing.

Clothing, accessories and shoes; videos, DVDs and games; and airline tickets, rounded up the list of most popular e-commerce segments.

Retention isn't just a hot issue for adult paysite operators and tangible goods merchants, with 60 percent of consumers preferring to be repeat customers of websites that they buy from regularly, rather than trying a new vendor.

Of course, this figure could also be interpreted to indicate that 40 percent of customers have been unsatisfied with a particular vendor and are seeking an alternative source for the products or services they desire.

"This shows the importance of capturing new online shoppers as they make their first purchases," Burmaster said. "If e-tailers can grab them with a positive shopping experience, they'll likely gain their loyalty and their money."

Merchants looking for more clues as to how best to serve their markets will note that after consumers considered vendors they have previously done business with, general surfing (following links) was the next most popular way of finding products or services, followed by search engines and finally special offers.

While the online adult entertainment industry has its share of challenges, it's clear that more people are looking to satisfy their basic needs online and are willing to pay to do so. Getting consumers to send their discretionary entertainment dollars our way is still going to be the tricky part, however.