Its not matured enough to be considered by the government to be a legal currency in the financing system now,bitcoins has a long way to go to achieve this kind of stuff.Having stability will be the best resolve for that for bitcoin to be considered to be implented as main currency
As a legal tender of exchange it hasn't gained importance. But technically it is matured to be used as a currency. There were more people who prefer it for cross border transactions which takes a lot time as well a big process with the banking system. This way it is good to eliminate the use of banks. When something does the work of a bank it can be mentioned as a currency.