From the inbox:
Greetings from Amazon.com. You saved $1.69 with Amazon.com's Pre-order Price Guarantee! The price of the item(s) decreased after you ordered them, and we gave you the lowest price.
The following title(s) decreased in price:
SuperFreakonomics: Global Cooling, Patriotic Prostitutes, and Why Suicide Bombers Should Buy Life Insurance
Price on order date: $16.19
Price charged at shipping: $14.50
Lowest price before release date: $14.50
Quantity: 1
Total Savings: $1.69
$1.69 is your total savings under our Pre-order Price Guarantee.
Prices fall with falling demand or increasing supply. Do those rules work at Amazon.com? If so, what does it say about the market?