article-sample.xml

<manifest>

    <title>
        <content:text i18n-id="{{uuid}}">Duis filet mignon ground round officia.</content:text>
    </title>

    <categories>
        <category id="{{category_id}}" banner_id="{{banner_id}}">
            <title>
                <content:text i18n-id="{{uuid}}">Duis filet mignon ground round officia.</content:text>
            </title>
        </category>
    </categories>

    <articles>
        <article src="{{page_xml_uri}}">
            <title>
                <content:text>Article title</content:text>
            </title>
            <categories>
                <category id={{id}} />
            </categories>
        </article>
    </articles>

    <resources>
        <resource id="{{filename.jpg}}" src="{{sha256.jpg}}" />
    </resources>

</manifest>


<article>

<!--
  Article Header - REQUIRED
-->
<header>
    <!-- Defaults to full width, height?-->
    <cover-image src="{{sha256.jpg}}" />

    <!--
      Page title, displayed in page header - REQUIRED
        text-color: DEFAULT( primary-color )
        text-scale: DEFAULT( 1.8 )
    -->
    <title>
        <content:text i18n-id="{{uuid}}">Spicy jalapeno bacon ipsum dolor amet porchetta.</content:text>
    </title>

    <!--
    Page tagline, displayed in page header - OPTIONAL
        text-color: DEFAULT( primary-color )
        text-scale: DEFAULT( 1.0 )
    -->
    <tagline>
        <content:text i18n-id="{{uuid}}">Duis filet mignon ground round officia.</content:text>
    </tagline>

    <!--
    Author, displayed in page header - OPTIONAL
        text-color: DEFAULT( primary-text-color )
        text-scale: DEFAULT( 1.0 )
    -->
    <author>
        <content:text i18n-id="{{uuid}}">Duis filet mignon ground round officia.</content:text>
    </author>
</header>

<!--
   HERO - Page content - OPTIONAL
     content directly in the page, primarily used when no cards exist
 -->
<hero>

    <!-- Adds a bold style and padding/margin to simulate a section label
        text-scale: DEFAULT( 1.0 )
        text-color: DEFAULT( primary-text-color )
        text-style: DEFAULT (bold)
        -->
    <label>
        <content:text>Duis filet mignon ground round officia.</content:text>
    </label>
    <!--
      Paragraph section - OPTIONAL - adds padding/margin around content
        text-scale: DEFAULT( 1.0 )
        text-color: DEFAULT( primary-text-color )
    -->
    <paragraph>
        <content:text>Meatloaf beef ribs pork belly boudin ut andouille nostrud fugiat turkey exercitation dolore velit
            pig pork. Cupidatat elit et, dolore nisi laboris incididunt prosciutto commodo fugiat sint eiusmod jowl.
            Proident dolore ball tip tri-tip ut veniam.
        </content:text>

        <content:image src="{{sha256.jpg}}" align="[left,center,right,justify?]"/>

        <!--
            Button - OPTIONAL
                color: DEFAULT( primary-color )
                text-color: DEFAULT ( primary-text-color ) [ applied to content:text node ]
        -->
        <content:button type="url" value="https://give.cru.org">
            <content:text i18n-id="{{uuid}}">Label</content:text>
        </content:button>
    </paragraph>
</hero>

</article>

I'm following. There would still be listed

<categories> 
  <category>...</category>
</categories>

somewhere though, right?

Based on this screenshot, would "One guy gives you his very honest..." be the tagline or hero->label?

yeah, the main list of categories could still live in the manifest.

@frett in that screenshot, the line you mentioned would be "tagline"