For some reason I have become embroiled in fixing Usability issues with XBMC. This is hampered by both the usual 'UI design by programmer' issues of open source, and that like many media projects of it's era they adopted the Skinable Interfaces mantra.
I entirely endorse
Makali's comment on what should happen to programmers who suggest Skinable Interfaces. I also suggest that had cars been designed so the end user could apply an entirely different dashboard arrangement, including adjusting the location of steering wheel and arrangement of the gears; one in ten cars would have been driven into ditches because the driver had set it to an inappropriate or badly designed skin.