Bitcoin is going down right now. It's about 500USD/BTC. I wonder what is mental support price for miners under which they would prefer to buy btc instead of mining it? That would be more or less mining cost. So what is the current actual cost of mining 1BTC?
You can use a mining calculator to compare the available hardware's output, then add fixed cost (hardware) and variable cost (the cost of manpower, power, replacements, maintenance, etc).
I am assuming you mean ASIC mining cost, as GPU mining has not been profitable for bitcoin for quite some time. I found a site which keeps track of ASIC deployment and also provides a mining calculator: http://minr.info/
Generally miners do a lot of work to find places with cheap power, you can find kWh rates here: http://en.wikipedia.org/wiki/Electricity_pricing#Price_comparison
Even though this may seem unrelated, miners can also use GPU or Scrypt ASICs to generate alternate coins (and then convert them to bitcoin), which may be cheaper than generating/buying bitcoins. You can find a lot of information about various algorithms and a mining calculator for many alternative algorithms here: http://www.coinwarz.com/cryptocurrency
Beyond all of this, it is worth noting that bitcoins can be generated by any computer capable of doing such calculations, and that there are at least some people who do not pay for the power that they consume, and sometimes not even the hardware (such as college students and hackers, respectively). Therefore the price of mining a bitcoin can be next to nothing or actually nothing for some people who do not play fairly, and who will mine full-force at virtually any price.
The actual cost varies necessarily due to a number of factors. It's actual cost is subjective as it is interminably subject to change as a result of aforementioned factors.
Electricity is free in some parts of Africa. Liquid nitrogen cooling techniques compounded by walls of ice miles deep in northern and southern poles are not open to anyone, much less blogged about conclusively. The best mining equipment will be open source public discourse eventually, maybe. . . But that is not the case today.
^^^if you have ever looked at the A. S. I. C. Mining manufacturing concerns, you will see a profoundly disturbing justification for the above skepticism; they all "pretest" their machines for months beyond their "preorder" slated release date. Preposterous, that the pre-orders be postdated months after the promise, and even then, just a few lucky would-be miners actually receive equipment as advertised. (see Butterfly labs)
When the terrible miners finally rolled their first batch out, they could only be overclocked by the best in the world to put up 1.6Ths. (seen Teraminer)
(see what I mean)