Google tests a new feature that replaces the URL with the site's name in search results snippets. David, who noticed this change, says that he searched for [madvertise] and "most of the results looked normal, with the website title, snippet and URL. However, two search results displayed the website name instead of the URL. In the close screenshot, the 6th and 7th results show 'LinkedIn' and 'Facebook' respectively, in the position where the URL should be."
Google has always tried to make search results listings more useful, but replacing the address with the site's name doesn't add value and draws unnecessary notice to the results from a list of hand-picked popular sites.