Google Webmaster Tools

– tell Google that www.domain.com and domain.com are the same
– check robots.txt files
– discover crawl errors that Googlebot saw
– see some spam penalties

All this is happening because Sitemaps is renaming itself and tackling a wider scope: all of webmasters. There’s even an official Google blog for webmasters now at https://googlewebmastercentral.blogspot.com/

Matt Cutts
Answerer: Matt Cutts