Google Chrome has always been a little more than a browser: it's optimized for running web applications, each tab runs as a separate process, the interface is minimalistic and there's even a task manager. "We realized that the web had evolved from mainly simple text pages to rich, interactive applications and that we needed to completely rethink the browser. What we really needed was not just a browser, but also a modern platform for web pages and applications, and that's what we set out to build," said Google in September 2008.
Google's blog announces a natural extension of the Chrome project: an operating system for netbooks. "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. (...) Google Chrome OS will run on both x86 as well as ARM chips and we are working with multiple OEMs to bring a number of netbooks to market next year. The software architecture is simple — Google Chrome running within a new windowing system on top of a Linux kernel."
As people use more and more web applications, the operating system becomes less important and it makes no sense to pay for it. The desktop mail client could be replaced by Gmail, the calendaring application could be replaced by Google Calendar, the office suite has lightweight alternatives: Google Docs and Zoho, it makes more sense to use an online feed reader like Google Reader, your scientific calculator is less powerful than Wolfram Alpha and you'll rarely need a video player when you have YouTube, Hulu and other video sites.
This idea is not new and there are already operating systems optimized for the browser. For example, Good OS announced last year Cloud, an operating system that "integrates a web browser with a compressed Linux operating system kernel for immediate access to Internet, integration of browser and rich client applications, and full control of the computer from inside the browser". If Google manages to create a great user interface, the new operating system could be very successful.