Google has always been in heated competition with Microsoft. We thought that the competition was becoming hot again when the company behind the dominant Windows OS launched their new search engine Bing with much fanfare. But that may be nothing compared to the bombshell Google just dropped.

Google announced on their blog tonight that they're releasing an operating system: Google Chrome OS. While the company already has a mobile operating system in Android, this new one will be based off of Chrome, Google's web browser. According to Google, the open source OS will be available later next year and is primarily targeted at netbooks to start. From the Google blog:

"Google Chrome OS is an open source, lightweight operating system that will initially be targeted at netbooks. Later this year we will open-source its code, and netbooks running Google Chrome OS will be available for consumers in the second half of 2010. Because we're already talking to partners about the project, and we'll soon be working with the open source community, we wanted to share our vision now so everyone understands what we are trying to achieve."

It is designed to be a lightweight system, just like the Chrome browser. Unfortunately, Google didn't divulge many other details, and it will be a while until anyone gets their hands on it. Clearly though, Google's setting the stage for a major battle with Microsoft. Just as Microsoft is trying to break Google's stranglehold on the search engine market, Google may be trying to do the same with the Windows-controlled market.