Google has announced more detailed site error information feature in google webmaster tools. This update is useful when you are looking for the source of your site errors.Google has broken down each category into more specific errors. Categories are: DNS Server Server Connectivity Robots.txt fetch This feature will help to provide a better analysis of your site’s health. Now we hope that these changes will make site errors even more informative with details. You can read about this change into details through the webmaster tools help forum.
Great, just checked them and everything is ok on my side. It's actually quite a great utility, especially the Robots.txt.