errr it is the real deal, Microsoft wouldn't put that out there if it weren't can you imagine the black lash if it were faked?
I don't doubt you. Stuff is always available to MSDN subscribers really early.
But that video is not on a Microsoft website, or even on a MS youtube channel. There's little in there to prove authenticity.
Bootup time is only important really for laptop and netbook users who will be turning their PCs off and back on frequently as they move from place to place.
What they would be better devoting time to is making windows run better without hogging resources.
If you have a look on the MSDN link I posted you'll see the video there
Doing this people can save battery life on the laptop/tablets by powering down when they don't need them on and have the benefit of quick boots
It's also available to ANYONE who goes to dev.windows.com and wants to download 1 of 3 ISO's ( I recommend the 64 bit with Dev tools ISO, around 4.8Gb but has all the tools and the Metro apps work, whereas the 32bit ISO the apps don't work, actually here's the link
http://msdn.microsoft.com/en-gb/windows/apps/br229516/Win8 is also going to need
less resources or equal to that Win7 machines, most likely less from what I've read.
I understand they are aiming for the touch screen market, but they are not appealing to my 32" desktop with flight simulators 
Good thing you can access the normal Windows 7 like interface then and disable the ribbon in explorer
