This is fairly old news since it was announced July 7th, but I was on vacation and missed it. I'd read something about a Chrome Operating system but I thought someone was confusing Google's Chrome browser with an OS...turns out that's not the case and Google really is developing an OS for PC's.
Next year at this time you should be able to buy a netbook with the Google Chrome OS. Netbooks are just the start though since the open-source OS is being designed to work with computers from small netbooks to full-size desktop systems. The OS will run using the Linux kernel and promises to provide fast start-up/web access times, no viruses, and computers that always run as fast as when you bought them. The main app installed on the PC will be the browser and there's no slowing down your computer as apps are added since every app you need is on the web in this vision of computing.
Start up and shut down times have become more and more of an issue as Windows has gotten to the point where it can take minutes to boot up and get online or shut your computer down. I'm happy that this laptop with a 2.6.30 Linux kernel and ext4 file system takes 43.5 seconds to power-up and connect to the wireless router (actually a little less since I have to manually select which kernel to boot and enter my user name and password) and about 15 seconds to power down. The Google OS is supposed to be online in "a few seconds" - I assume that's with a solid state hard drive.
As a big fan of the Ubuntu Linux distribution, open-source software in general and someone who's been happy with anything Google I've tried - I'm looking forward to seeing how the free open-source Chrome OS works.