In case you are wondering whether crypto-currencies are legal in your country, check this out.
Some countries treat them as foreign currencies while others consider it as digital property, but not same as currency. Approaches differ across countries though adoption (read, awareness) is gradually increasing.
NY Department of Financial services came out regulation draft to buy/sell/hold or transfer crypto-currencies . This ‘bit-licensing framework’ has now become guiding document for other countries looking to adopt crypto-currency regulations.
While blockchain is designed to be de-centralized, unregulated market to trade digital assets, governments are looking forward to regulations in space of bit-licensing which will decide on parties allowed to transact in virtual currencies and related disclosure/record keeping requirements.
Such developments are slowing down adoption by central banks which face regulatory hurdles to adopt it widely.
This would be a critical piece of puzzle to solve before blockchain becomes commonplace.