Windows 8 uses essentially the same code base as 7,  but it's had work done to make it more efficient. There are dozens, if not hundreds, of (fairly technical) articles analyzing and reviewing the changes out there.

I've only had it installed for a few days so I'm still finding new / improved feautres, but so far:

I routinely have to copy or move big chunks of data from my workstation PC to NAS devices across a 100 gb/s network and there are massive improvements here: not only is it a whole lot quicker, there's better feedback while it happens. 

A lot of the under-the-bonnet (under-the-hood) tools have received much needed attention, to the point where (for example) third-party de-fragging utilities aren't necessary.

I've seen in the other thread something about Win8 only lets you have 2 windows open at a time. That's nonsense.

The thing that smacks you in the face at startup is the Metro interface; it also appears when you hit the start button on the keyboard. It is highly configurable, potentially more useful than the old Start thing, and disappears when not needed. Yes, you'll look at the mainly tablet-related stuff in there, skim through the toys and then 'unpin' what you don't want.

So, apart from the obvious cosmetic changes, Windows 8 is just like Windows 7, but a bit faster and better thought out.

Edited to add screen shot.

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Windows 10 x64 Pro - Intel Xeon E5450 @ 3.00GHz (x2)

PoserPro 11 - Units: Metres

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