My CPA wants me to provide her with the value of the bitcoin when I mined it vs when I sold it.  It doesn't have to be the same btc, that's a daunting task to calculate.  She just needs a number for the books.  She needs a basis value for when it was mined vs when it was sold.  And she's treating it like short term gains, like stocks.  I'll use the difficulty vs my hash rate to calculate what I mined.  I can look at my payout history on btcguild, but that doesn't reflect the date mined, just the date it moved it from btcguild to my wallet.  My CPA doesn't know what to do, we're really just guessing.  There are simply some huge deposits into my checking from coinbase that need accounted for,  that's what we're doing.  If you never sell any btc, you need not report anything.