Thanks Mark for this one. X-bit labs is reporting that DirectX 10 will be not released for Windows XP.

During a DirectX 10-related event in London, UK, Richard Huddy, ATI Technologies’ software developers relations chief, said that Microsoft’s Vista will integrate DirectX 10 and DirectX 9 APIs for different types of hardware, but the current Windows XP will not get DirectX 10 support, as suggested some rumours earlier. For end users this means that to get the most advantages of the new-generation graphics processing units (GPUs), the new OS will be required.

Microsoft Will Not Release DirectX 10 for Windows XP – ATI