It is the Google Webmaster Central coming out of beta stage. And they have enabled commenting on the Webmaster blog also – an unusual step from Google for its blogs. They officially done the announcement as follows –
We’ve come a long way since our initial launch of the Sitemaps protocol in June 2005. Since then, we’ve expanded to a full set of webmaster tools, changed our name, listened to your input, and expanded even more. 2006 was a year of great progress, and we’re just getting started. Coming out of beta means that we’re committed to partnering with webmasters around the world to provide all the tools and information you need about your sites in our index. Together, we can provide the most relevant and useful search results. And more than a million of you, speaking at least 18 different languages, have joined in that partnership.