Chrome OS is still an early project and it's not yet ready for primetime, so the first Chrome OS notebooks will be available in mid 2011. For now, Google focuses on notebooks, but that will change in the future.
Google realized that cloud computing wasn't successful 15 years ago because there weren't great Web applications. Now there are a lot of great apps and Chrome Web Store is the place where you can find some of them. We'll see a lot of iPhone and Android developers creating web apps that work in Google Chrome, but also work in other browsers.
Check the New York Times web app, which has a beautiful interface, it's customizable and also works offline.
Chrome now has 120 million active users, up from 40 million users one year ago. This number will grow next year, when people will buy Chrome OS devices. Google hopes that Chrome OS will become one of the top 3 operating systems in terms of usage, but it won't be easy to achieve this. For some people, a Chrome OS notebook will be the main computer, for others it will be a secondary device. What's important is that users will have a great platform for running web apps, a computer that doesn't require maintenance, it's really secure and easy to use.
Chrome OS is "nothing but the web". It may seem limited, but it's actually open ended. It's a platform that lets you access the web instantly, that's always connected and always in sync, it's built for sharing with other people, it's up-to-date and it's constantly improving.
Chrome OS is the obvious extension to Chrome. Why use a bulky operating system that requires maintenance, it's slow and insecure when you can switch to a lightweight operating system that's fast, free and refreshing? If Chrome can open in 3 seconds, why can't the operating system load so fast? Chrome OS is an operating system that doesn't need drivers to print, doesn't need an antivirus to be secure and doesn't need to store or process your data. Chrome OS could make computers exciting once again and the best part is that you won't have to use it to benefit from its influence.
Further reading and exploring:
* Google's blog post about the Web Store and Chrome OS
* Chrome Web Store
* Chrome OS website
* Chrome OS pilot program for US early adopters: get a free Cr-48 Chrome notebook.