As of this writing, on December 1, 2009, the Blogger website is generating 59,000 visitors a day. For the month of November 2009, it received over 1 million visitors. Traffic appears to have peaked at 68,000/day in the last week of November 2009, but it is still quite high. At that time, we were in the Top 215 blogs on the Internet.
Prices for ads run by the week, two weeks, month and 3 months. Prices at the moment are extremely reasonable for a high-traffic website.
One issue on the site is that traffic comes from all over the world. Therefore, the best ads on this site that would target the largest number of visitors would be ads for name brand products or products that are sold worldwide, since visitors come from all over the globe. Lately, we have many visitors from the Pacific Rim, particularly Korea.
In addition, many visitors do not speak English, at least as a first language. Therefore, name brand products sold worldwide or products sold worldwide with websites in multiple languages, or even products targeting, say, Koreans, would work best.
At the moment you can hit 1 million viewers a month all over the world with your ad for a very low price. I’m not sure how equivalence works with print media, but I assume that that may be akin to a 1 million/month circulation magazine.