The following info has been submitted by a few people now, and I had also ran across it way back in October ... so I was positive we'd already run it. However, a thorough search this morning has proven me wrong. So here it is, several months after it should have run...whoops!
In 10.3, you can now navigate the System Preferences panel by typing the name of the panel you wish to activate. Once the System Preferences window is open, just type "Cl" and the Classic pane will highlight; "Ac" to jump to Accounts, etc. You can also use the arrow keys to move around, but typing the first part of each panel's name is much quicker.
Once a pane is highlighted, you can open (launch) it by hitting the space bar. From there, you can use the Show All keyboard shortcut (Command-L) to get back to the "Show All" preferences view.
Mac OS X Hints
http://hints.macworld.com/article.php?story=20040206080835280