Microsoft is planning a "big" announcement on Monday that may have forced Google's hand in launching Chrome OS, tech pundit and Rackspace blogger Robert Scoble claimed today. While a non-disclosure agreement prevents him from providing further details, he implies that the news will have something to do with web apps, which will be the way software can run in Google's upcoming platform.

The Windows producer is unlikely to produce its own web-based OS as the company's core businesses still center around native apps, including Office and supporting third-party code in Windows. A recent preview by CNET, though, may provide clues. Microsoft has been developing an experimental web browser nicknamed Gazelle that is designed to secure web apps. Expanding on a sandboxing approach similar to what Google uses in its Chrome web browser, Gazelle isolates the web apps themselves rather than whole pages, in some cases restricting apps on the same page. The approach permits advanced web code to run without allowing malicious pages to infect the browser or the operating system. Apple's Safari only just recently implemented a very limited version of this concept that prevents plug-ins from crashing the entire program.

Gazelle is in a rough state and still uses the basic Internet Explorer engine; it's also not anticipated to directly translate into a future version of the company's browser. Company researcher Helen Wang all the same says the prototype is an example of the "right way to go" for all browsers and hints that the technique could eventually arrive in an official release.