John Carmack and Tim Sweeney Q&A
 

We'll be making a UE3 benchmark available several months before shipping UT2007 on PC, in order to encourage the hardware folks to optimize their drivers. We're not doing this now, because at our stage in development many aspects of our rendering pipeline aren't fully optimized, and if we encouraged IHV's to optimize for it now (by releasing a benchmark), they would end up wasting a lot of time optimizing code paths that aren't reflective of a final, shipping UE3 project.