I recently wrote about using gphoto2 to both set Owner and Copyright information on a DSLR, and using it for tethered shooting. For those of you who are adverse to command lines, the very promising Entangle is now in Debian unstable.
It does everything I have previously written about and more. Not only can you shoot tethered and see your photos appear on screen, you can change all the camera settings from the GUI including aperture, shutter speed, ISO, camera mode, etc.
Furthermore, you can use it for remote shooting. Stick you camera on a tripod, and shoot away from the comfort of your laptop. Highly recommended.