Well Amazon did it to me again. The week it's supposed to be released (according to Paizo's page) they cancelled another discounted book pre-order I made claiming they can't get the book... from Paizo. (only one of the biggest and most reliable RPG publishers). This streak of dishonesty in pricing is unfortunately nothing new from them. 
Here is part of the message I sent them:
Why do you keep cancelling my book pre-orders. This is far from the first time you have done this to me and I expect the outcome to be the same.
I ordered the Advanced Race Guide from you with a preorder discount that you offer on most products from this publisher. The publisher, Paizo, is the seller of the most popular game (yes, at times, their sales have even surpassed Wizards of the Coast who sells D&D). Their print runs are NOT small. ...
In the past, when you have done this to me, I have purchased the book elsewhere then come back to the Amazon page to find that you magically found a source for my cancelled book. But it is now listed without any discount. Why offer these worthless "guaranteed" pre-order discounts if you are not going to honor them.

Here is part of the message I sent them:
Why do you keep cancelling my book pre-orders. This is far from the first time you have done this to me and I expect the outcome to be the same.
I ordered the Advanced Race Guide from you with a preorder discount that you offer on most products from this publisher. The publisher, Paizo, is the seller of the most popular game (yes, at times, their sales have even surpassed Wizards of the Coast who sells D&D). Their print runs are NOT small. ...
In the past, when you have done this to me, I have purchased the book elsewhere then come back to the Amazon page to find that you magically found a source for my cancelled book. But it is now listed without any discount. Why offer these worthless "guaranteed" pre-order discounts if you are not going to honor them.