ETA:  Problem resolved.

If you posted a wish listed book the requestor has 48 hours to accept unless the book was auto requested. If they had ordered a book directly from your bookshelf the one hour would apply.

ETA From the help Center:

When you Post a book that another member is actively wishing for, the book will be offered to the member immediately  - it will go into a Wish List Hold on your My Account main page. Your account will show the notation below:

• Reserved On: (date)
  Status: Waiting 48 hours for other member
  to confirm that they still want this book.

• When the Wishing member confirms that she wants the book, you will be notifed by email.
• If she/he declines the book (or does not respond within 48 hours), your book will then be offered to the next member on the Wish List for that book.
  • You will not get an auto-email notifying you of this cancellation; the offer will just be passed along.
  • If no other members are wishing for that book, it will go onto your Bookshelf. (If this happens, you will get an auto-email telling you that this has happened.)

Normally, though, wishlisted books that I post show up on my main account page under "Wish List Holds" during that 48-hour period.   I posted another wishlisted book that is curently showing up there.  However this book does not. That's what has me confused.

Go to your bookshelf and see if the book is there.  If it is, look for an exclamation point on the right hand side. That means there is a wisher for the book.  If the book is not there, maybe there was a glitch and try to repost the book tomorrow.