Just to post something vaguely related to the benchmarks in the OP's link... my rig (specs at lower left) pulled 44 fps in the "Tropics" demo, dx9 mode, set to 1280x1024, 4xFSAA, other options on high. In OpenGL mode it tested at 37 FPS. In DX10 mode, I get nothing but a black screen (the benchmark is running at 300+ FPS, but no graphics are rendered).
Any idea why the DX10 modes fail? Graphics card (GTS 250), or Windows 7 issue?