As mentioned in the Driver Station limitations/bugs thread, the DS only supports joystick devices that conform the the USB HID standard. This means that the Xbox 360 controller won't work, but a majority of joysticks and gamepads will. If the joystick does not need any additional drivers to work in Windows, it should work with the DS.

Some of the Beta teams tested the following joysticks/gamepads.

Logitech Dual Action Game Pad
Logitech 3D Pro Joystick
Saitek P2600 gamepad

It would be helpful if as other teams test other joysticks, they were posted here so everyone could benefit.