So I found the solution for this problem. For whatever reason, when the Bluetooth Device Setup Assistant runs on Leopard (instead of Tiger), the setup will quit after selecting printer, and the Printer & Fax System Preference comes up.
When this happens, simply press the add “+” button in the lower left corner and it’ll bring up another device window. Select the Bluetooth tab in this window. Then double-click on the printer you want to add wirelessly.
For whatever reason, this is how it chooses to add a Bluetooth printer, instead of directly through the Device Setup Asst.