Bitfloor's "average price" for buys When you buy bitcoins with USD or other currency on Bitfloor, it quotes you an "average price" per bitcoin and says the "actual price may vary" once the order is completed.

The "average price" stated changes periodically, but it always lags the present actual market price on Bitfloor.

Question 1: when I hit the BUY button, what price do I get?  The "average price" or the current market price on Bitfloor?

Question 2: how does bitfloor calculate this "average price"?
The average price is calculated by taking into account the current market conditions (i.e. other buyers/sellers) against the amount you wish to buy/sell. Given that the market is always changing, your actual average price may vary. When you finally place a market order, the system will execute against the best available prices at the time.

If you would like to have more control over the pricing and order execution, use limit orders. These may not execute immediately (depending on how you price them and their size) but you will be able to control those factors.