The CFTC is involved in the Tether case, so I'm thinking the government will end up taxing them as commodities, which is actually great. I mean, its going to be almost impossible to enforce taxes if you do business on non USA exchanges but they'll try.
If cryptos are taxed as commodities, theyll be subjected to much lower tax rates than income tax rates.
Encryption monetary income may cause up to 20% - 30% of the tax, but it depends on whether the digital currency can be regarded as a kind of business income or capital income.