A new topic would be similar to someone writing a message part way thru the communication book instead of adding it immediately following communication that had been taking place. If the message were in a binder in the closet or on the contact's desk it could be very easily overlooked.
We have taken steps here to see that does not happen.
This is different than being notified of a
REPLYTo receive an email notification of new topics (ie new pages in a book you use)

1-Make sure you are in the main screen of the book (or board). You can verify you are in the right screen if you see 'Subject' where we show the red arrow to the left.
2-Select the Notify link directly below the company logo.
3- You will now receive a notification when a new note is placed in a book that you have access to.
4- Notifications can be sent as a text message to your phone.