I'm really against taxing bitcoins because it defeats the main feature of bitcoins which is its decentralization. If it gets taxed, the goverment takes over bitcoins one by one. Imagine that you have to pay a percentage of the bitcoins for transaction fees and then pay for tax. That's too much if you ask me.
Not really though the point of bitcoin wasnt being able to evade taxes or anything, the point was not being tracked on EVERY single thing we do so its pretty alright