As I entered my car last night, I noticed that I could not see the switches on the door panel. (ie. window, seat) I have to think that they were illuminated. The entire panel is dark. Do I have a multiple bulb outage, or is there no lighting on the panel?

 

There are at least three discrete bulbs in the drivers door (probably 4 if you have seat controls). It unlikely that they would all die simultaneously unless there was some kind of electrical failure causing a surge. Otherwise there might be a broken wire or bad connection in a harness.

Replacing door panel lights in the X300 is 'fun'. Two of them are very easy to access, but replacing the mirror back light requires disassembly of the whole door card (from the looks of it the seat control back light will be the same). Follow this link and scroll down to see pictures and instructions for replacing the back lights: Backlights