Spotted by Google Operating System first, I then covered it yesterday at Search Engine Land - Google is testing displaying the site name as opposed to the site URL in the search results.
Here is a picture showing the site name in place of the URL:
Here is a picture of how one would typically see the site URL:
Google has been testing the placement display options of the destination/display URLs within the search results a lot this month. First by moving the URL above the snippet and now this.
Forum discussion at Sphinn.