You can now associate a "featured image" with any topic in your project, in addition to a text description. You can find the settings for these new options in the Topic Options tab. These images can be used to make attractive title pages for your chapters in both PDF and HTML-based output. It is used for the title images in both the CHM and PDF versions of the documentation of this project, for example.
The screenshots below show featured images used in the title page for a chapter in PDF output on the left, and in a CHM help file on the right. The description text defined in the Topic Options is also inserted as part of the title page.
You can learn how to use this feature in PDF in the help of the Print Manual Designer program used to edit your PDF layout templates. How to use it in HTML-based output is explained in the featured images tutorial project that you can access in the Welcome section at the top of the Project Explorer on the left.