In an attempt to combat Microsoft's monopoly on the Windows OS market, Google announced that the Chrome OS would be available sometime next year. Google will be targeting the "Netbook" market first, then move on to more powerful PC like Desktops.
"Google Chrome OS is being created for people who spend most of their time on the web, and is being designed to power computers ranging from small netbooks to full-size desktop systems"
The new operating system is intended to be lightweight so that it starts up quickly and you can get going without having to wait too long for items to load up and other processes to run.