Creative has announced their ALchemy project which is aimed at providing Sound Blaster X-Fi drivers for Windows Vista. In Vista, Microsoft has removed the Hardware Abstraction Layer(HAL), which DirecSound and DirectSound3D require. While games that use OpenAL still work, those that use DirectSound would face problems, until now. The project is still in the beta phase, but it seems promising.
"The good news is that the Creative ALchemy Project allows you to run your favorite DirectSound3D games on Windows Vista as the developers intended - with full hardware accelerated 3D Audio and EAX support! This is done by translating DirectSound calls into OpenAL. In order for this to happen, a couple of files need to be installed into each game directory. This is handled automatically by the ALchemy installer - but can also be performed manually by advanced users."