Hey guys, I just finished a project that interfaces a DSLR connected to the Arduino(via a USB shield) and uses Bluetooth to connect to an Android device. (I created the app too)
The end result is, well, full manual control over most the the camera's features like Aperture, Shutter speed, ISO, etc.
Tutorials/code available here:
http://code.google.com/p/yanis-android-wireless-camera-controller/
Let me know what you think, and feel free to join the project development!