Bought an ATI 7950 to mine, apparently the $400 card will profit $485 (after cost of card/electricity) over a year according to this calc:
https://bitclockers.com/calc
That's 120% gain on one year's investment. If everything checks out and it's easy to convert BitCoins to cash or make purchases with, that's a damn good return, $485 isn't much, but percentage wise, it's a lot.. if things pan out I'll consider buying more cards. Now that return will depend of course on the btc price and however the difficulty / output changes. One way or another, it will most likely not be 120%, and if so, sheer coincidence, it's so volatile. I still don't fully get the system, but what the heck, sounds fun and I'll figure it out as I go, I always learn more by doing.. besides the card comes with FARCRY3 BLOOD DRAGON!!! Once a year I like to sock away and play out one FPS, that game looks so intentionally cheesy and cliche, it's right up my alley.
At 21:00 in the interview from the OP, he mentions how the processing power of the card is the facilitation of the system, and the payment is the reward for doing so.
The currency has value as long as you can find one person to exchange with, it does not matter how widely recognized the currency is. Learning about this goes well with the Ascent of Money video I'm watching now.
What I find funny about this.. if GPUs can turn a profit, I can imagine a house getting raided with a tip from the power company (marijuana grow ops are always happening here) -- cops knock down the door and find an entire house rigg'd up with GPU cards... fans spinning like mad, house at 100F...