the shiny bit feels colder than the rest, but I still guess it is painted plastic. It is a slightly lifted cap over a hole in the black eggo cover which gives the impression of half-closed phones, but there is a plastic film underneath so they really are closed (but there is a mod to gain bass which involves making a pea-sized hole in the plastic film after popping the cap off and putting the cap back on making them half-closed after all)
well spotted tekdroid, but they are DVD's and the pinkish thing in the background is me

indeed... I prefer these over the PX100!