BitCoin would most likely not be considered money or currency under US law. US law can be extremely broad in application because of the doctrine of stare decisis. French law is based on civil or continental law which is even more code based and thus likely to be less broad in application.

There will need to be legislation written to define BitCoins but, at least in the US, this will be almost impossible to do if it is to pass Constitutional muster given doctrines such as void for vagueness under due process in contrast to ignorantia juris non excusat.