Blog network 9rules has organized its more than 120 member sites into some 30 categories - dubbed 9rules Communities - in preparation for the launch of an upcoming blog ad network, reports ClickZ. Some sites are independent blogs that have enjoyed success prior to joining. Some are business-to-business blogs, such as Om Malik's GigaOm and Paul Boag's BoagWorld. Others are consumer-focused, such as the entertainment blog Crap Filter.

"These changes will make the 9rules Network even more useful for our readers. For advertisers what this will mean is targeted advertising on a number of blogs that they can count on being high-quality," Paul Scrivens, president and CEO of 9rules, told ClickZ.

Once the ad network launches, advertisers will be able to buy ads across a category, on specific sites, and on category pages on the 9rules site and in search results, Scrivens said.