With 13.2 million unique U.S. visitors in January 2011, the Huffington Post was the ninth most popular non-financial news website visited from home and work computers in the U.S. Its new ‘sister’ site, AOL News, was the fourth most-popular with 22.1 million U.S.-based unique visitors. AOL News is AOL’s second most popular channel – behind MapQuest – and, in effect, the Huffington Post becomes AOL’s sixth most popular property just behind AOL Messenger/AIM (with 13.3 million uniques in January) and ahead of AOL Music (with 13.1 million).

AOL’s network of websites attracted 76.2 million unique U.S. visitors in January 2011, or 39 percent of all active U.S. web users. Visitors to AOL’s websites spent an average of 1 hour 58 minutes during the month, viewing 85 pages on average. Based on average visitor January figures, each Huffington Post reader adds almost 12 minutes of time and 18 pages to the AOL portfolio – a total of 155 million minutes and 237 million page views.

Although the Huffington Post had 13.2 million U.S. uniques in January, almost 10.2 million of them also visited an AOL website, thus the net effect of AOL’s acquisition is almost 3.1 million new visitors or 1.5 percent more reach into the active U.S. Internet population. There is also a strong overlap between the Huffington Post and AOL News. In January 2011, 44 percent of visitors to the Huffington Post also visited AOL News; with 27 percent of AOL News readers also visiting the Huffington Post.

It’s not just about the extra readers the acquisition brings but the type of visitor. Although the audience makeup to AOL News and the Huffington Post is broadly similar, the latter is more concentrated around certain demographic groups. For example, the Huffington Post has a higher concentration (34%) of 18-49 year old females compared to 29 pecent for AOL News. The Internet average is 27 percent.

Although the audiences to the two entities are spread similarly geographically across the U.S., it is notable that the Huffington Post is more likely to have visitors from the West Coast while AOL News tends to have a greater concentration of visitors from New England.

The Huffington Post audience also tends to be more highly-educated – 44 percent hold a bachelor or post-graduate degree, compared to 37 percent for AOL News, 31 percent across the entire AOL portfolio and 25 percent across the entire web.

A very encouraging element of Huffington Post reader behavior for AOL concerns who consumes content. Visitors from households with incomes above $150,000 account for twice the percentage of total page views consumed on Huffington Post (12%) than they account for on AOL News (7%) and across the entire Internet (6%).

Those with a bachelor’s degree account for 50 percent more of Huffington Post content (33%) compared to AOL News (24%) and the Internet average (22%). Most starkly, those with a post-grad degree account for almost three times the percentage of Huffington Post content (34%) than they average across the whole Internet and AOL News (both 12%).

The NY Times’ website drew just over 20 million unique visitors in November — a 10% increase over unique traffic to the site last November.

Meanwhile, MSNBC saw 41.9% year over year growth, reaching 41.8 million unique visitors last month, according to Nielsen. 

MSNBC edged past CNN Digital Network (CNN), which drew 41.5 million unique visitors during the month — a 27% increase over its November 2007 unique audience.

Despite the conclusion of the U.S. presidential election, The Huffington Post (ranked #21) continued to see the fastest growth among the top 30 sites. The site’s unique audience increased 270% over November 2007 — to 7 million unique visitors.  However, Huffington’s unique audience declined from October 2008, when the site’s unique visitors grew by 448% year over year to 8.1 million.

Fox News Digital Network was the second fastest growing site among the top 30 — up 131% over November 2007.

Among the top 30 newspaper sites, the Minneapolis Star Tribune (ranked #12) saw the fastest growth.  The site’s unique audience increased 265% over November 2007 — to 3.5 million unique visitors. 

The Detroit News (ranked #25) was the second fastest growing site among the to 30 — up 232% over November 2007.

Overall, all but one of the top 30 online news outlets and all but four of the top 30 newspaper websites attracted larger online audiences in November 2008 than they did the prior November.

View the top 30 newspaper websites for November in Editor & Publisher.

View the top 30 online news outlets for November in Editor & Publisher.

Read coverage of Nielsen’s findings on MSNBC.com.

MSNBC Digital Network

Surging interest in the Beijing Olympics and the U.S. political conventions, which occupied back-to-back weeks in August, may have played a part in boosting MSNBC past its close competitor, Yahoo! News, Editor & Publisher reported Tuesday. 

In August, MSNBC drew 52.2 million unique visitors — 12 million more than Yahoo!’s news portal, according to Nielsen.  During the prior August, both Yahoo! News and CNN Digital Network edged past MSNBC.com, with 34.3 million and 31.7 million unique visitors, respectively, to MSNBC’s 29.6 million visitors.

Most of the news websites in Nielsen’s top 30 ranking attracted larger online audiences in August 2008 than they had the prior August, and all but two of the top 10 sites showed double-digit percentages of growth.

Beyond the top 10, TheHuffingtonPost.com, ranked #23 by Nielsen, and the Daily News Online Edition (#30) showed especially large year-over-year audience growth.

TheHuffingtonPost.com saw its unique audience jump by 291% — from 1.3 million in August 2007 to 5.1 million last month.  Meanwhile, the Daily News Online Edition grew by 103% — from 2.2 million unique visitors in August 2007 to 4.5 million in August 2008.