Google's Chrome OS may force Microsoft to reinvent its Windows operating system into a product that takes full advantage of the web and that can move more nimbly across devices, according to analysts.
Microsoft is unlikely to have been surprised by Google's announcement. From what has been revealed about the Google Chrome OS - which won't be available until the second half of next year - it aims to bring the ease of use that Google has brought to web-based applications, such as search and chat, to netbooks and eventually to full-size PCs.
A Google OS is "something Microsoft has been worried about for a long time," said Matt Rosoff, analyst with Directions on Microsoft. He called it "the first significant threat to Windows in a very long time," although he said the threat may not become fully evident for another 10 years.
Still, Google's plan to exploit the popularity of low-footprint, low-cost netbooks could accelerate the need for Microsoft to reinvent the bulky, PC-centric version of Windows for consumers and businesses, as more people begin using applications that live on the web rather than on their local hard drive.
It could also eventually force the company to develop one core version of Windows that can be used on any device - be it a smartphone, netbook or PC - similar to the way Apple moved downstream by adapting its Mac OS X software for use on the enormously successful iPhone, analysts said.
Microsoft has not been immune to the problem of marrying the increasingly web-centric world with the desktop world, in which applications run on a thick client with a resource-heavy OS, but until now the company hasn't had to worry too much about it.
With Windows the de facto standard on PCs, people have been for the most part content to wait for Microsoft to deliver new versions of the OS, and connect to the web and their favourite applications from there. And many business customers are tied to Windows by long-term contracts and application dependencies, which has kept them loyal to Windows for better or worse.
For its part, Microsoft has been working to hone its web-based services and applications, and even removed some software from the forthcoming Windows 7 - such as email and photo-editing software - in favour of web-based versions that are more lightweight. Windows 7 will be available on PCs later this year.
Microsoft also has a research project called Midori that envisages a next-generation Windows in which the OS becomes more Internet-centric and eliminates dependencies between local applications and the hardware on which they run, although the company has not said how this might fit into Windows' commercial future.
The emergence of netbooks, however, changed everything, taking not only Microsoft but also the rest of the hardware and software industries by surprise, and providing a vehicle for Google to make its move into the OS market.
"Netbooks showed up and startled everybody," says Forrester analyst Frank Gillett.
But while netbooks provide a way for Google to get a foot in the door of the personal computer market, the company certainly has aspirations to challenge Microsoft on more traditional PC form factors as well, he said.
Google's challenge and its implications usher in a new phase for the OS market in which both the hardware that the OS runs on, and the OS itself, become less important, and a device's ability to keep people connected to the Internet and their applications and data that live there becomes paramount.