Olivier Kyte is in that Google search favicon desktop results test and he noticed that for some search result listings that the snippets are missing the URLs from showing up. Instead you just see a favicon, a hashtag and an arrow down.

Here is the screen shot he posted on Twitter - I tried to replicate it in multiple browsers but I am not in this test group I guess.

Again, this seems to only impact the interface Google is testing with favicons on the desktop results, not the main user interface. I guess Google has a bug to fix with this interface test before releasing it more widely to the public?

Forum discussion at Twitter.