Many people have noticed a new googlebot user agent in their log files recently. This new entry in the log will look like Mozilla/5.0 (compatible; Googlebot/2.1; +http://www.google.com/bot.html). Way back in March, googleguy over at webmasterworld forum mentioned that they were testing this new user agent and would roll it out when they believed it make a smooth transition. Apparently, six months later, that time has come.
So if you were wondering what this new user agent in your log files was all about, now you know!