I could not find any information on this anywhere else, so I though I should post my find here.
So I was using the multitouch test app because I was curious how many multitouch contacts the phone supported (4) and I noticed that the digitizer seems to run completely from the top of the screen down through the capacitive buttons at the bottom. When moving the multitouch point around, it remains activated if you drag your finger down into the soft button area and continues to work if you move around there. It also reports coordinates and it indicates that the digitizer is 480x862. Now I know that the buttons are not quite part of the screen like the Samsung Continuum, but it is something after Samsung's playbook there. It seems that the buttons are either just 4 small round LCD screens or they are one continuous one that is covered by the black backing. If you shine a light at the buttons you see the 4 round screens.
Now, this observation may not translate to anything, but it makes me wonder if it would be possible to actually change the button appearance. It also makes me wonder if it would be possible to have a program that could rely on swipe gestures on the touch buttons since the digitizer is continuous. Maybe a way to implement swipe up to open the recent apps? Or swipe left and right to switch between recent apps? I don't have the programming knowledge to implement this, but hey, it could open the door to something interesting.