Ever since OS X 10.0 Chetah, System Preferences has displayed a fixed set of baseline Preference Panes plus user additions. The baseline set has changed a bit throughout the years, but nothing fundamental has changed with the User Interface. Lion adds a new trick — the ability to hide selected Preference Panes.
In Lion, if you click and hold the “Show All” button, you’ll see a popup list of all the Preferences. You can select one from the list, just as if you’d clicked on the icon.
System Preferences in Lion
What’s interesting is the “Customize…” option at the botton of the list. Selecting that will show each Preference Pane with a check box badge.
Uncheck to suppress
If you unckeck one of the items, then click “Done,” that preference will no longer be displayed. You can recheck the box to bring it back.
What’s even more interesting is that you can do this as an Administrator, a Standard User, or even as a user managed with parental controls. Changes made in that account apply to that account only and not to any other account. At least in my testing so far.
It’s not clear why Apple added this feature. Certainly, an Administrator can lock critical Preference Panes to avoid tampering, so this new feature doesn’t seem to be intended for sysadmins. Perhaps, and this is just a guess, it’s a convenience for users who accumulate too many Panes (or pains) and want to simplify the display. In time, we’ll know more.