In the spring, the mining "difficulty level" was 10 million. It is going reach a mining difficulty level of 1 billion in the next few days. Many ASIC machines are coming online and that is creating some serious competition for the remaining Bitcoins. On the plus side, all of this trading has increase the payoff for miners as they also process transactions.
Okay I have one more stupid question. A bitcoin is roughly worth $700. If I’m selling widgets for $70 and I accept bitcoins are you and I co-owners of the coin or do I have to give you $630 cash when you purchase my widget?