As far as I can tell from skipping through the video that is NOT Windows 8 - it doesn't have the Metro interface, it looks like a jazzed up Windows 7 to me.
Yeah it is Win7 running software to give it some win8 style functions like large quicklaunch icons that are more reminiscent of iOS but also the touch friendly login screen. I suspect when Windows 8 does hit, Samsung will also update their hardware with a Series 8 slate, if nothing else just to fall in line with Microsoft's 8 branding.
If I was going to get one of these, it would be nothing more than to mess around with the touch functionality Win8 beta so I reckon I'll wait for the next wave of hardware to be released post Win8 launch.