A Windows 8 demo was just released.  Looks really cool.  Check it out at Previewing ‘Windows 8’ as well as Microsoft’s Windows 8 Demo From D9 (Video) and Windows 8 partner demo.  If you just want screen shots, check out this article on eWeek.com.  Also read How Windows 8 could change everything which would enable the consumer to bring their latest and greatest Windows 8 device into the enterprise and have IT push down the Enterprise Desktop and run inside a Hyper V client container on the employee’s own Windows 8 Device.

UPDATE: The Windows Developer Preview is a pre-beta version of Windows 8 for developers.  Download here.

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Building Windows 8 Blog