I'm trying to make sure that our application will run well on Windows 8. Currently I'm using the Windows 8 Consumer Preview, and there is no driver that supports the Intel Media SDK, especially QuickSync.
Intel Media SDK will be available for Windows 8 (Desktop mode). But as you point out, there is not yet an official Intel graphics driver (this is required for HW acceleration via Media SDK).
For Media SDK HW acceleration, you will have to wait until this driver becomes available. As of now I cannot give you an estimate on when this will happen.
In the meantime, Media SDK (SW codecs) can still be used on Windows 8 preview. Keep in mind though that some of the code samples may not work as well as they do on Windows 7. Adaptations to Windows 8 is work in progress.