The Inquirer have sourced some brief details on Futuremark's next big 3DMark release, this to to be based purely around DirectX 10, meaning you'll need Vista to run it.

A blog posting by Nick Renqvist (3DMark developer) mentions that this next iteration of 3DMark will contain DX10 specific volumetric effects and will boast "cinematic rendering" quality, something we're yet to truely experience on our home PCs.

THE UPCOMING iteration of 3DMark will only be available for Windows Vista and DirectX 10.
In a bog post to the Futuremark website, Nick Renqvist says that "the next generation 3DMark will be Windows Vista only, and will require DX10 compliant hardware."

So why no fallback to DX9? Nick cunningly anticipates this point. "You may ask: Why not fallback to DX9 then?" Yes Nick, we just did. "Well, we already have a Vista enabled DX9 benchmark (3DMark06) and the last three 3DMarks have all been DX9".