The software author or company by this time will have tested it on 8.
Also, dx9 apps/games seem happy on later versions of directx.
i want to buy black ops 2 and i want to play it on an HP ENVY m6 with:
operating system: Windows 8 single language 64-bit
processor: intel core i5 6gb ram 2gb dedicated graphics 2.5 GHz
black ops 2 says it needs directx9.0c compatible sound card so i really dont know if it will work on my notebook