Actual production cost of one single bicoin is aroundt $530-$550. Any price below $500 is a steal. Buy now or regret years later. With difficulty ever increasing miners are getting screwed now cause anyone mining now is running at a loss.
Evidence Please? This might be true of people who have to buy overly expensive miners - this is not true for those who have desigened and built their own chips.
Take an antminer s1 running 180 Ghs @ 400w taking 303 days to mine 1 full btc,
Price of Antminer S1: $200
Electricity cost : 400w x $0.12 /kW x 24h x 303 days = $349
Total: $549
Note that is still not factoring in the difficulty increase every 2 weeks which actually means it'll actually take more than 303 days to mine 1 single btc.