Next 3DMark will be Windows Vista Only
 

The next generation 3DMark will be Windows Vista only, and will require DX10 compliant hardware. You may ask: Why no fallback to DX9 then? Well, we already have a Vista enabled DX9 benchmark (3DMark06) and the last three 3DMarks have all been DX9; 3DMark03 has one test which requires SM2.0, 3DMark05 requires SM2.0 for all tests and 3DMark06 uppers the requirements for two tests to SM3.0. I think both we and the rest of the world are ready to step into the next generation - DX10.

http://www.yougamers.com/blogs/nick_r/