In a perfect world price is determined by supply, demand, and the velocity of the currency. It is slightly different if the currency is pegged to an asset such as Royal Mint Gold, or a gold backed Ruble or Yuan.
Bitcoin is a bit different, and can be the victim of price manipulation by the elite bankers. Because the available supply is fairly small and restricted it is vulnerable to pump and dump activities. The frenzied activities of new speculators tend to amplify these price movements.
Yes, that is why others are pushing for regulation to avoid price manipulation.
For the OP miners do not determine the price as other posted it is still the basic of economics supply and demand. Price will always be determined on what the people are willing to pay for.
