Whilst agreeing with Laura's comment I would say, and this may not apply where you are or because you don't use public transport, etc., but I-pods, much like cellphones, have become the new mugger's must-have and are owners are identified by their distinctive white ear-pieces and the wires connecting them to the machine.

http://news.bbc.co.uk/1/hi/england/london/4583327.stm

If this is not a problem in your area then go for the shiny, white, new, virginal earpieces.