Unable to leave well enough alone, I found out that ATI released new versions of its drivers today for all platforms including Linux. The latest version for Linux is ati-driver-installer-7-11-x86.x86_64.run, or 8.433. I followed the standard --buildpkg procedure and then installed the deb files.
The performance appears to be a tad better (a tad being about 5% faster, with smoother operation overall). I can enable more Compiz Fusion eye candy, but I can't run OpenGL applications or movies if Compiz Fusion (Appearance Preferences | Visual Effects) are enabled. I have noticed that playing movies, without Compiz enabled and using VLC as the player has cut CPU loading nearly in half compared to using 8.42.3. And with Visual Effects enabled, the desktop is really beginning to look nice.
Now, if it would just all start magically working together without one feature trampling on another. I still have the hard choice between desktop effects (Compiz) or OpenGL and smooth video playback, but not both.