Windows 8 will have better media playback and recording, but it will balance using hardware acceleration to save battery life and using the CPU when it gives a better result.
Audio will use hardware acceleration more because that does improve battery life. There will be post-processing to take out blur, noise and shakey video filmed on a phone or webcam, and support for more codecs including AVC and as-yet-undetermined 3D video codecs (stereoscopic3D support is coming, for games and for 3D movies in Media Center, but there are format issues).
Microsoft talks about sharing 'with nearby devices'; one way that will work is adding the Play To option currently in Windows Media Player to the browser for HTML 5 audio and video content, so you can play it on any device that supports DLNA, another is APIs to let other software do the same.
That will work with DRM content, if it's protected with DTCP-IP (digital transmission content protection over IP) or Microsoft's own PlayReady and hardware acceleration will speed up DRM decoding.
There's also a new 'remote display' option that will let you send your screen from a laptop to a large monitor (which will use DirectX hardware acceleration and the same multimonitor interface that's already in Windows 7, but for wireless displays as well, which could be an Internet-connected TV - Microsoft refers to 35% of TVs having network connectivity by 2012 and wonders whether to prioritise Internet TV over further improvements to broadcast TV).
