^^ The SoC is same, so basically same CPU and GPU. RAM is also same. In fact the only differences are the screen size/form factor, led flash and the OS.
It is just my guess that if both the wave and the galaxy S have the same Hardware specs,,,the benchmark will run better on wave because of the lower screen size.....
^^ The screen is the same resolution (480 x 800), only that its in a 3.3" form factor. If there is any difference in performance, it would be because of the different OS.