Microsoft just showcased the developer preview of Windows 8, its next generation operating system for computers and tablets.

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And its next-generation operating system, Copland, which is designed to work with both Macintosh and IBM-compatible machines, is due to be launched next year.

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Another entrant, Jolla, says its 'Sailfish' platform is a second-generation operating system like BlackBerry's BB10 and is easy to use because it has a gesture-based user interface and is designed to avoid patent litigation.

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