Have a look at the URL for this news item (the first created in this way). The script checks to see whether there is a news folder. If not it creates it. Then it checks to see whether there is a folder for the current month. If not, it creates it. Finally we create the News Item in the appropriate folder, and redirect to its metadata_edit_form.

post_article.py:

 #create a news item

 news_folder = 'news'
 article_id = str(DateTime().strftime('%d%H%M'))
 current_month = str(DateTime().strftime('%b%Y'))

 portal_root = context.portal_url.getPortalObject()

 # make sure we have the news folder object
 if hasattr(portal_root, news_folder):
    news_object = getattr(portal_root, news_folder)
 else:
    news_object = portal_root.invokeFactory('Folder',news_folder)

 #now get the folder for the current month
 if hasattr(news_object, current_month):
    current_news = getattr(news_object, current_month)
 else:
    news_object.invokeFactory('Folder',current_month)
    if hasattr(news_object, current_month):
        current_news = getattr(news_object, current_month)
    else:
        print "Unable to create folder %s in %s folder!" %  (current_month, news_folder)

 current_news.invokeFactory('News Item', article_id)

 o = getattr(current_news, article_id)
 destination = o.absolute_url() + '/metadata_edit_form'
 context.REQUEST.RESPONSE.redirect(destination)

 return printed

Note:

The solution is not scalable. The main problem is the absolute URL is ${portal_url}/news/MonYYYY/DDHHMM. So you can only create one uniquely identifiable news item per minute. If you were running a large site, this wouldn't be enough. Even adding in seconds/milliseconds might not be enough. The solution (as implemented in Plone) is to append a random number to the end. The before creating the item, you check to see whether an item with that URL already exists. If not, you regenerate the number and try again (repeat ad nauseum). Its a very ethernet approach :)