Warning - Old Content
This post is quite old, and it might not apply anymore, or maybe there's a better way to do the same thing nowadays. Take with a big grain of salt.
After upgrading my laptop to Ubuntu 12.10, I decided to re-run the glmark2 tool to see if performance changed at all. Unfortunately, I seem to have lost some graphical oomph with the upgrade. My laptop’s new score is 697, using the same fglrx driver as before. Hopefully that will work itself out after a few weeks’ worth of upgrades/bugfix packages.
Update: switching to the fglrx-updates driver seems to have slightly improved things, and may have reduced the overall lag when opening applications. With the fglrx-updates driver, my glmark2 score is 712. That improvement may just be random chance though.