re: mining, the question is:  when is the income recognized?

If I start a mining business, I am expensing the hardware and the electricity, pool management fees, etc.

If I keep all the coins I've mined for two years, there would be no income generated by my mining business until I actually decide to exchange it for fiat.  My business would be showing a loss for those years.  I am recognizing the income when I sell off my BTC.

If I report the current value of BTC when they are generated as income, I would pay tax once, and then once again on any gains if the value of BTC were to appreciate.

What approach is everyone else taking?