pipelined tessellation is similar to the effect you see in crysis going from medium texture settings to high texture settings when looking at the ground rock textures you see the rocks actually appear vs being a flat image, the technology behind how a graphics card can render that result now makes the fps increase that much better because it's actually rendering a 3d model of the object

the 460 is REALLY cheap for the performance you get it looks like (btw what resolution and settings are those benchmarks at?)