Apparently in an attempt to bloster their sagging classified advertising numbers, a large group of newspapers and Zillow have agreed to join together to spread classified advertising to Zillow online. Newspaper classified advertisers can choose to put their ad on Zillow.com. On the flip side the newspaper publishers will be able to use Zillow's real estate info to add to their own websites.
I don't know if that'll work to increase classified ads. Most real estate agents have been shying away from newspaper classifieds and turning to increased internet exposure instead.