On the vaistech it displays on the LCD panel of the radio (I have a satnav display, but the 05 model does not have dvd player or mp3 readout on the big screen)
My one can display playlist name and track name or playlist number with track number. I can cycle through by pressing the text button on the radio.
Yes, I have routed the cable to the glovebox. I agree fantastically neat solution, 1000s of songs under control of the head unit with no obvious signs on show.