I've just posted an article (about) on WPF development on the Telerik forums. I will repost it as a single comprehensive article on this blog during this month, but I'd like to put a copy of the code discussed on the forum here for everybody to get.
hmmm... oh dear. I cannot seem to add attachments to this blog post.
download it from here (or http://www.bluemarble.co.za/downloads/radribbonbarx1.zip)