Seems like yahoo is trying to mix up certain things into their search results. Recently they have announced that they are going to test adding Favicon's into their search, an experiment which is intended to improve the search experience for users.
Yahoo mentions that there are many favicons which are already popular on the web now. So For example, when a user searched for "Expedia" or some other search which matched a popular domain, then that same favicon will be coming up next to the URL in the ad(check the image below). Yahoo is expecting that use of favicons in the search results will help them to improve the user click through and there by quality score experience.
However this is just an experiment which is intended to rolled out only to few selected advertisers. If you are interested in trying out this new feature sign up for this experiment but remember that if you are bidding on your own domain name and you have a favicon icon file on your site, you may not be eligible to participate.
Note: A favicon is a 16x16 pixel squared icon related with a particular website or webpage