At present it seems that the de facto code for bitcoins seems to be BTC. There has been some discussion of this over on the forums and an entry on Wikipedia, but I thought I'd ask the question here to arrive at an easily recognised community answer.
So, if bitcoins ever became ratified as a currency under ISO 4217 (paywall, PDF) would it be given the code BTC? If not, then what other serious contenders are there?
The normal rule is (two letter country code) + (letter), although that's arguably already been broken by the Euro having EUR instead of EUE.
BT is the country code of Bhutan, whose currency has the code BTN. If anyone will object to BTC for Bitcoin, it'll be them.
According to wikipedia, which is never wrong, multi-national currencies use the X prefix. XBC is taken by "European Unit of Account 9", but XBI is available.
