First, we all pray to whatever gods there be that capital gains will be what the IRS applies...

Anyway, I think it's probably realistic to file based on the creation date of the coins that are sold, and not on the purchase date (advance or otherwise) of the device used to mine them.

I wonder about the deduction for this type of equipment in the case where you haven't yet received it, but have already paid for it.  I believe that will have to be treated as any other depreciable equipment asset - so you'll be able to set up your depreciation schedule starting from when you paid, and not from when it is actually received.  I know for a fact that that's how balloon-making machines are treated, having bought one and taken delivery in the following tax year.  The catch there is that you later have to show that the equipment was actually used against the income you later claim.  But the big catch may be that, rather than making something tangible, you're creating an intangible good:  I'm unfamiliar with that, in re taxation.  Will bitcoin even be considered a 'good'?  I'm unclear on that.