Last week, headlines were made when Arianna Huffington, the founder of The Huffington Post, sold the popular news blog to AOL for a cool $315 million. It was an interesting announcement for sure, yet another indepent news source being gobbled up by publicly traded conglomerate, Huffington writers speaking out on Arianna cashing out for millions while they were never paid and most interestingly, the analysis behind the acquisition.

Nielson, my favorite place for random hard-to-find numbers, recently shared a bit behind AOL's reasoning. 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. By comparison, 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. 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.

However, I'm not sure AOL was purely interested in a 1.5% market increase when they wrote Arianna a $315 million dollar check. Rather, I think they were interested in tapping into the kind of people who read The Huffington Post. Interestingly, the Post is popular among women — (34%) of 18-49 year olds — as opposed to the web's average of 27%. Also, Huffington Post dramatically skews toward more educated viewers (oftening translating into more affluent viewers as well). In Huffington's case, 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%).