I was just thinking about this the other day. Living in the US, the definition of Cryptocurrency is rather murky. The government considers it a currency, hence the need for currency exchange license for crypto exchanges operating in the US, including FINCEN rules regarding Know Your Customer (collection of identity information for all customers).
Yet the IRS has defined it as property, so capital gains taxes would apply anytime it is exchanged for goods or services. Here is where it gets even stickier with Steemit, since your are being paid for work, which typically becomes a taxable event at the time the work is performed, not when the item of value that is transferred in exchange for work is sold.
My guess is the IRS would be very willing to accept taxes you pay on earnings from crypto sales or Steemit earnings, but if we would have a pull back at the end of the year, I believe they would be reluctant to allowing a loss deduction for the decline in market value.
It is going to be an interesting period that we are entering!