It seems that it's largely governed by the power costs of generating the bitcoins. I think folks are assuming that computing power is free, but they're talking about using a laptop to generate a block of 50 bitcoins taking 5-10 years. It's an investment opportunity to bind a ****-ton of GPUs together to create the currency. You better be really good at math to see if it's worth it or not
This is pretty interesting the more I look into it...
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