$10 GH/s by the end of 2014.
There are already units offered at less than that. Cointerra is $6.99 per GH/s.
If you believe that Cointerra will be successful and if you believe that the price of BTC is going to stay under $150 then my $10 estimate wouldn't make any sense.
Well even KNC batch2 (Nov) is down to $11.50 per GH/s. By the time every company has paid off their NRE and delivered their first batch of hardware difficulty is going to be much much higher, and there likely is little appetite. $10 I think is unreasonable. Anyone offering $10 per GH/s in early 2014 is likely not going to see a sale. by mid or late 2014 it is going to look downright silly.
The marginal cost of production is closer to $1. Given finite economical capacity and multiple competitors it is kinda hard to believe that 1000%+ margins will be sustained.
If Bitcoin is $500 by mid 2014, and a person can earn 10 Bitcoin with the miner over a reasonable period of time, they will be willing to pay somewhere close to $5000 for it. If you can mine 10 BTC with a 500 GH/s miner and the price of Bitcoin is $500, then the price per GH/s a miner will be willing to pay will be ~$10. Miners haven't proven themselves very good at math so far. If manufactures want to shoot themselves in the foot by drastically reducing price per GH/s, they have the margins to do it but I think they will determine the price by what they think people are willing to pay, not what it costs them to produce the miners.
Competition could force them to reduce prices but buyers falling over themselves to buy at current pricing is going to limit how far they reduce prices. If the manufacturers are as bad at math as miners are, you may be right and they will reduce prices right down to the point that they fail to make a profit and take the miners right down with them due to the higher network hash rate.
I personally hope it doesn't get to that. They should reduce the prices slowly over time once they are able to deliver within a few days of a a buyer placing an order. This will mean higher profits for them to develop the next generation and really it will mean higher profits for miners because the network will not grow as fast.
$500-$1000 Bitcoin and $1/GH/s just doesn't make sense to me.