It is pretty, but I guess a simple tree map (example: http://news.bbc.co.uk/2/hi/technology/8562801.stm http://news.bbc.co.uk/2/hi/technology/8562801.stm) where

It is pretty, but I guess a simple tree map (example: http://news.bbc.co.uk/2/hi/technology/8562801.stm http://news.bbc.co.uk/2/hi/technology/8562801.stm) where the sizes of the various rectangular pieces give some idea of the %age would have been much better.