Google introduced the world to WebDriver back in 2009. It was a framework that provided automated testing of apps. While there was already an established webapp testing framework on the market in Selenium, the two technologies merged to create a single software that could handle all the rigamarole that comes from testing web apps.
Google announced today the launch of Google+Open+Source+Blog%29">ChromeDriver, a Chrome-centric version of WebDriver. It offers the same functionality and testing features of the WebDriver API. So what's the difference? The Selenium/WebDriver application will still be developed by its current team, whereas ChromeDriver is being developed by the open source Chromium team.
If you were hoping for more of an announcement than that, sorry, that's it. Google is just taking the development burden of WebDriver for Chrome under their own wing and slapping a new name on it. In their defense, Google has created an excellent resource page for those who develop web apps on Chrome that need testing.
I make it sound kind of inconsequential, but it's a good move on Google's part. The traditional WebDriver team can now narrow their focus having one less browser to worry about and Google can make sure Chrome gets the best version of WebDriver possible. It's a win-win for everyone.
ChromeDriver is compatible with current stable, beta and dev versions of Chrome. Older versions are obviously not supported. There will be new versions of ChromeDriver released twice a month. You can download it at the ChromeDriver page. Happy testing!
Google has been on a roll lately with providing more tools for Chrome developers. There was the recent release of inline installation that makes access to apps easier than ever. They also released tools that make it easier for developers to port high-quality console games to Chrome as well as create high-quality graphics in-browser with WebGL.