I assume the news sources will be configurable at least in xwiki.properties (in the same way the extension repositories are configurable).
I thought the plan was to have a single XWiki.org source (that we control and which we can change at any time to include forum news if we want) and to allow other sources, e.g. for a sponsoring company like XWiki SAS (which would be used to promote Pro Apps). So my expectation is that XS will have by default two news sources configured:
- XWiki.org source
- XWiki SAS source (as the top sponsoring company)
similar to how we have e.x.o. and store.xwiki.com repositories configured in xwiki.properties.