Today Someone made a Google page on sites.google.com and offer to download the beta version of chrome OS. You can check the page here. Many big blogs including Gizmodo posted and removed the posts because it was fake. You may found the torrent downloads of Chrome OS beta but stay away from such kind of claims. Here is a little detail about the Google Chrome OS.
Google Chrome OS is a light weight, open source operating system targeted at netbooks. Google OS project is a natural extension of Google Chrome. Speed, Simplicity and Security are the three key aspects of Google Chrome OS. According to Google OS team “As we did for the Google Chrome browser, we are going back to the basics and completely redesigning the underlying security architecture of the OS so that users don’t have to deal with viruses, malware and security updates”