I have Windows 8.1 on one of their Surface Pro machines. I feel it only necessary to check out what changes/improvements are brought about by Windows 10; my hope is that they will have managed to further improve the experience when it comes to switching between tablet and laptop-replacement modes. (As-is, it isn't like there's something specifically lacking, but there's room for innovation).
Beyond that, I tire a bit of the 8.1 implementation of the Start menu (though I have no reason to install the 3rd party replacements), so if I can find a good use for the live tiles on the revised Start menu, thing'll be peachy.
â€¦I probably shouldn't charge forward with a new OS given the fact that software may (will) break until updated, but I've taken that risk before (new hardware/new OS/new form factor) and survived, so why not?