Ah Ok so you are working on it (found the github page), I lost the overview over the past months as the last Ubuntu release worked quite well. I will try to understand the code and if I am able to I will help you out there.
So I pointed out that there is no 2D accelleration. Let me clarify that I did not meant the whole output of the driver won't be rendered by GPU but only the accellerated video output as it is used by VLC or Gstreamer if you set the video output to X11 as guilhermer did.
If you display a video with better resolution it will be slow and interrupt other works as the whole rendering is done by CPU.
(I hope I'm right on that, as I said I'm a lot more into software than driver/X development).
Does your driver work with Natty ATM? I patched an old release just to get it through compiling but it stopped working today after an update of X. Vesa does not work either right now... might be my fault too.
I will test the code on git tomorrow and start looking into it