wouldn't that be shitty if you turned a 10,000 profit but didn't pay the tax only to have them lost or scammed and then have the irs start an audit from linking addresses then telling you that you owe a few thousand to them...WOOPS! (profit from trading within an exchange fiat to btc over and over ,then coining out in btc to hide it) or in the case of gox bcz it takes too long to wait for a cash out !