Although sites that offer Internet services like free e-mail are growing fast, search engines, portals and online communities account for the bulk of all online traffic in the United States, according to a report released Monday by Nielsen//NetRatings.
One out of every three Americans visits a portal site like America Online (NYSE: AOL) or Yahoo! (Nasdaq: YHOO) each day, giving the portal category an audience reach of more than 92 percent, the report said.
"Search engines, portals and community sites have established themselves as a mandatory part of every surfer's online habits," NetRatings vice president of e-commerce Sean Kaldor said.
The findings support 
those of Jupiter Media Metrix, which
issued a report earlier this month saying that four sites dominate the Web.
Jupiter found that AOL, Yahoo!, Microsoft (Nasdaq: MSFT) 
(Nasdaq: MSFT) and Napster
together account for more than half the time
Americans spend online.
E-Commerce on Edge
The Nielsen//NetRatings report found that e-commerce sites were the only category to register a decline in traffic from January to May.
E-commerce sites saw 42.1 million visitors in May, reaching 40.8 percent of the Internet audience -- a decline of 3.4 percent since the start of the year, according to the audience measurement firm.
Not only do portals -- the No. 1 category on the Web -- capture the most attention from Web surfers, they are increasing stepping into the e-commerce realm, analysts say. Portals are evolving into e-commerce brokers, according to a study released in April by Forrester Research.
Additionally, a Yankee Group report earlier this year said that sales at portal sites grew faster than standalone e-tail sites during the 2000 holiday season.
At Your Service
The second-busiest group of Web sites in May after portal sites were telecommunications and Internet service sites, attracting 72 million visitors, or close to 70 percent of the Web population, Nielsen//NetRatings said.
According to the report, telecom and Internet services sites attracted 4.7 percent more users in May than in January, compared with a 2.4 percent growth rate for search engines and portals.
"Telecommunications and Internet services sites continue to play a
significant role in daily Web usage," Kaldor said. "Key to their growth has
been the overwhelming success of free e-mail services."
That means sites like MSN and Yahoo!, which "have aligned themselves in both of these top two categories," are "ideally positioned to dominate surfer mind-share and wallet-share," said Kaldor.
That's Entertainment
Entertainment sites also saw robust traffic in May, attracting 69 million users, or 67 percent of all Web surfers, Nielsen//NetRatings said.
The entertainment category is the third most visited sector on the Web, the audience measurement firm said, even with a decline in traffic to Napster. The controversial music site has seen its visits drop after it started blocking transfers of copyrighted music in order to comply with a court injunction.
Computer and consumer-electronics sites were the fourth most popular category on the Web, garnering 48.37 million visitors, or 46.9 percent of the Internet audience, according to Nielsen//NetRatings.
AOL on Top
AOL Time Warner sites comprised the most visited single group of sites on the Web in May, reaching an audience of 78.66 million, according to the Nielsen//NetRatings report.
Yahoo! was second, with 69.98 million users, followed by MSN at third, with 61.8 million, and MSN parent Microsoft at fourth, with 38.62 million, the report said.
Lycos, Excite@Home, About.com, Walt Disney
Internet Group, Amazon and eBay
rounded out the top 10 sites in May.
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