I am in the UK and have not yet cashed out any coin.
However when I do, I understand from a phone call to the HMRC and a cross check of their website, that I will be needing to pay capital gains tax over a certain tax free threshold, reset annually.
So although there is no 'Bitcoin Tax' the act of changing Bitcoin in to Fiat creates a Capital Gain.
So I just have to make sure that I stick within the £10k or so annual threshold and I don't pay a penny.
However, if I do happen to need to or want to exceed that threshold, will I pay the tax? Of course I fucking will, I don't need or want the hassle of a fine or jail time. Anyone who says otherwise is, in my opinion, a total imbecile.
+1+1 to the two last posts. We can not afford having people looking at Bitcoin as a way to cheat on their taxes, nor having a lot of people getting fined for not filing their income in Bitcoin correctly. Taxation guides for each country are being compiled in different threads for the challenged, as I myself was, at the start at the year when the numbers suddenly added up, and my hobby had become an income.