HTML Email Newsletter Generator from WordPress, Joomla or any CMS for that matter

Does anybody know of an add-on for WordPress, Joomla or any CMS that will automatically ‘fill’ a html email newsletter template.

Here’s my proposed work flow:

1. User adds articles to CMS

2. CMS add-on generates/fills pre designed html email template

3. Email template is exported ready to be imported into Mailchimp, Campaign Monitor or the like.

Is this possible?