To promote their television programs, network executives have turned to online advertising - specifically on blogs, where inventory is cheap and ads can target groups likely to watch the programs - reports MediaPost. VH1, TBS, and several PBS affiliates have promoted their shows via the BlogAds ad network. TBS has advertised "The Real Gilligan's Island," "Sex and the City," and "Minding the Store," on entertainment-related blogs; PBS has promoted documentaries about Robert F. Kennedy, Fidel Castro, and sex researcher Michael Kinsey.

BlogAds displayed 12 million impressions for PBS's documentary about Kinsey. According to a PBS publicist, advertising on blogs offered an inexpensive alternative to targeting politically minded consumers: "There aren't a lot of places where you can spend $1,500, or up to $5,000 and get that much exposure and to such a targeted audience." A TBS spokesman also said the high return on investment and the ability to reach "influencers" is what attracted TBS to advertising on blogs: "They tend to be an efficient media buy."

BlogAds doesn't use CPM; rather, it charges based on length of time, ranging from one week to three months, and on blog popularity. A week of the most expensive ad space, the premium spot on Daily Kos, costs $5,000; in a recent week the site had received more than 5 million visitors.