According to the Inq's summarization of what's going down, the Alky Project will eventually allow anyone to run DX10 not only on Windows XP, but on WinXP with DX9 hardware. Of course, it's going to be via the use of wrappers, so the performance question looms large. I personally can't wait to see the benchmarks...

"Although this sounds like a fairytale, Cody claims he reverse-engineered the Geometry Shader code, and that users will be able to run Windows games intended on the Mac OS X on x86-based Macinteltoshes as well as Linux."