Preorder items will not delay the rest of your order and will not increase your shipping cost. Items ship out as they become available.
Booksamillion.com allows you to reserve selected titles or products that have not yet been released for sale. In many cases, you will receive the item in a separate package on the same day you could purchase the item in a store.
You will not be charged for your Preorder item until it ships (although the original pre-authorization amount will be for your full total).