As reported Google sent out a comic book unveiling the Google Chrome browser. Google now also officially announced Chrome on their blog and says that the beta version of Google Chrome will be available for download today.
Google's reason for launching a new web browser is their believe that they can add value for users and, at the same time, help drive innovation on the web.
Google is releasing a beta of Chrome for Windows today and is at work building versions for Mac and Linux.

The announcement of Google Chrome will increase yet again the amount of testing for web developers and web design agencies. Albeit Google Chrome is based on existing open source components it will surely behave differently for rendering and executing JavaScript. Maybe we users should just ignore this new browser and be happy with the browsers we have so far - enough is enough.
More details on the Google blog. See also the first Google Chrome Screenshot.