Information released by two different firms last week sheds some additional light on the nature of Wikipedia's continuing traffic growth. Internet traffic monitor Hitwise indicated that for the United States, roughly half of external traffic to Wikipedia comes from Google, with another 20% from other search engines. Meanwhile, competing analysis firm comScore reported that among US users, Wikipedia was one of the Internet's ten most popular websites in January.

Prompted by Danny Sullivan, Hitwise research director LeeAnn Prescott put together a summary of Wikipedia traffic coming from search engines. For the week ending 10 February, 2007, Hitwise showed 49.57% of Wikipedia traffic coming from Google. While Wikipedia's total traffic has increased significantly in the past year, Google's share has risen 19% in that period.

The overall proportion coming from all search engines, about 70%, has not changed as much; Prescott's accompanying chart indicates that traffic from Google grew largely at the expense of traffic from Yahoo. This is interesting when considering that in the competition for search market share generally, recent reports suggest that Google has cut into more of Microsoft's share than Yahoo's. Prescott also reported that among sites to which Google searches send the most traffic, Wikipedia was third behind Google Image Search and MySpace, at 1.87% of Google downstream traffic.

The issue of Wikipedia and search engine results has been the subject of some previous analysis, and the interdependent relationship gained significance in light of the media attention given to the financial health of the Wikimedia Foundation. Steve Rubel called for Google to revisit the possibility of defraying a significant portion of Wikimedia expenses, an idea that prompted its own media frenzy when it was discussed two years ago.

In the monthly report from comScore, Wikipedia sites ranked #9 on the list of most visited web properties in the United States for January, up from #13 in December. It should be noted that comScore ranks groups of sites in common ownership, not individual websites. The total number of unique visitors reported was 42,880,000. Measured against current population estimates, this would mean that of all the people in the US, about 14% visited Wikimedia sites in January. According to comScore's figures, the number of visitors is 24.4% of total internet users in the country.

While the number of Wikimedia visitors did increase 11% from the previous month, the higher ranking was also partly due to fluctuations in the other sites on the list. Web properties passed by Wikimedia since December included those of Wal-Mart, digital properties of Viacom and The New York Times, and the company formerly known as Apple Computer. Wal-Mart's website dropped significantly down the list as the surge of holiday shopping traffic ended.

As indicated, all of these figures are from the United States, as analysis of global internet traffic is less developed. Previous reports indicate that Wikimedia draws an even larger share from outside the US, however. On a global basis, comScore ranks Wikimedia sites as the world's 6th-most-visited web properties.