I've been following the 3d driver development for the r6xx/r7xx chipsets using the open source mesa drivers. Progress has been moving along well. In fact compiz has been working for the last week or so. Today, I did some testing and was able to play Quake3 at around 90fps (1280x1024) on my machine without using fglrx or catalyst. The only trick I needed was to specify.
on the command line.
However, I did need libdrm from git, the libdrm/linux-core kernel modules (you may need to regenerate initrd to use these modules) from agd5f's r6xx-r7xx-support branch, mesa git and the ATI ddx from git. Other than that I am using stock Fedora.
I also played vdrift and neverputt today, but etracer and neverball crash, so still more to do.