"proof currency" well I think you mean that people and countries recognize and accept BTC as real currency, and to allow using BTC in their shops. I think that can be possible, bitcoin is universal. Just in my opinion we will not be alive to see that, maybe some countries will do it in future, but for all countries to do that I think its hard.

I believe bitcoin is currency already, you can do a lot of things with bitcoins now, just like with any other currency. I don't see a difference. In recent times when I receive paycheck or some other income, or I pay something with my currency, in my head I calculate how much is that in bitcoins.

Just for fun 1 BTC is 59 441 Dinara ( my currency ). I work for half of that every month, maybe even less..