Quote Originally Posted by lat9 View Post
If this was an order placed by a guest, there's not address-book record created ... because they're a guest.
My store does not allow guest checkout. Customer need to create an account in order to checkout.

I also notice the following:

If I log in as a customer with email/password (i.e. returning customer or new created account), then add a product to my cart. After going to checkout and go to edit shipping address, there is no "add to address book" box being displayed.