it is also correct that the publish_date is the one from cr_revisions. without further action on the xowiki side, the publish_date was/is altered each time set_live_revision is issued, which happens per default in the save and save_new methods. With the changes, it is now possible to preserve the given date.
Since the "standard" publish_date is used, there are no changes required in this regards in malte's script.
concerning content vs. description: this is a matter of the point of view: when the full story is stored on a different server, one has just a small description (like an abstract) of the full story in an xowiki page (and in RSS), plus a link to the full text. Furthermore, in many syndication applications, the description is required to be plain text, so there are as well some arguments for this variant.
With xowiki it is quite easy to go both ways for representing news-items, even in one instance by e.g. using two different ::xowiki::Forms. As mentioned before, the default variant is the one using the text content.