I'm rather confused with this. is this an update or is this going to be a separate installation?
anyway, i'm using 8.1 right now and the only difference that I saw was (1) upon booting up, it now goes directly to the desktop, (2) Start button is now preset and (3) minor updates on the search function, resizing of the tiles, etc.
Honestly, I find the Start button useless coz it's missing the old functionality of the "Start" button. you're better off using those third-part software. Basically, the new "Start" button direct to the same tiles as that of Windows 8. I don't see much difference with Windows 8 and Windows 8.1 ..