If you have followed the instructions for renaming your Apple Bluetooth keyboard in OS X and it doesn’t work, the problem is actually an OS X 10.6 bug. I had the original version of OS X Snow Leopard without any patches and can confirm that the “Rename” option in System Preferences->Bluetooth does not exist. To fix, simply upgrade to the latest version of Snow Leopard (OS X 10.6.3 as of 5/11/2010)  They apparently brought back the “Rename” option in a newer version of Snow Leopard.

How to rename your Apple Bluetooth Keyboard:

• Update your OS X to the latest version (10.6.3)
• Go to the System Preferences menu
• Select “Bluetooth”
• If you see your keyboard on the left menu, select the bluetooth keyboard, click on the gear menu and select “Rename”.If you don’t see your keyboard, click on the plus icon to discover the keyboard and then add it.