Losses can only be taken on your initial investment amount if you have Bitcoins in MtGox. This means that if you invested $10k a year back, and your Bitcoins are now worth $1000k, you can only take $10k in losses.
Luckily I have realized my gains which means I can deduct $3k every year in losses with infinite rollover.
Luckily I have realized my gains which means I can deduct $3k every year in losses with infinite rollover.