Pare, the interior
came like that as part of the Inspiration Edition. The dark wood is actually Poplar (greyish to black) and slightly varies from the ML55 wood (brownish to black). But an untrained eye can't tell the difference between the two under certain lighting conditions [8D].
For example, take a look at this pic of the ML55 steering wheel in an Inspiration Edition interior. See how the ML55 steering wheel appears brownish-black compared to the rest?
Here is the same interior under different lighting. Note how the ML55 wood almost blends in with the rest of the interior?