System Preferences > Keyboard
Now the GUI presently allows you to set Key Repeat to a minimum value of 2, which for many folks, doesn't seem to be fast enough. We can change the value to 1, but before we do, take note of your current setting with the following command.
jbisbee@beni$ defaults read NSGlobalDomain KeyRepeat 30
Now to set the value to 1, we can use the following command. Unfortunately, you will need to reboot to have the change take affect.
jbisbee@beni$ defaults write NSGlobalDomain KeyRepeat -int 1
In the event you don't like the result, simply run the command again with your initial value.
jbisbee@beni$ defaults write NSGlobalDomain KeyRepeat -int 30
If someone knows the mac command to reinitialize, please share. :)