If you use the PowerPoint Broadcast feature within SharePoint Online, you will soon receive an email letting you know that the service is being removed and your library will be deleted.
As stated in the email, “This feature will be removed from SharePoint Online in 90 days (2 October 2012), and all data stored in the Broadcast site collection will be deleted.”
You can use two other ways to broadcast presentations to others in your company:
1. Use Lync Online (if you subscribe to the service)
If you have questions about the removal of the service, you can contact the product team by posting here: PowerPoint Broadcast and SharePoint Online.