There is no mention of the file dspace/config/news-xmlui.xml, and yet it is an important point of customization.
The file is a DRI template that appears to get merged with the page under constrction in the ArtifactBrowser aspect, see aspects/ArtifactBrowser/sitemap.xmap. It can contain a customizable greeting that appears on the site's home page.
The manual ought to mention this under XMLUI customization. The file is pretty much self-explanatory; the head element is a title, and the paragraph ("p") element following it is news text, in DRI markup.
There appears to be no way to add locale-specific versions of news-xmlui.xml, for news in different languages. If this is actually true, and not just a limit in my of understanding of Cocoon, that ought to be reported as a separate bug.