I've always been wondering why on some CX 747s (and I am sure other carriers' / aircrafts), the upper deck has a "honey comb" style panelling (like in http://www.flickr.com/photos/alaw168/324768493/), and some (most ?) others, it's a much more ordinary panel (like in http://www.flickr.com/photos/jaytong/2933343614/).
Does anyone know why ? Was it something changed by Boeing or was it an option that airlines could choose ? Just curious is all.