We have developed a custom addon for Interspire Email Marketer that allows you to publish and send RSS feed content (like blogs) to designated contact lists. The addon has a lot of configuration options that make it easy to set sending frequency, designated contact lists, full feed content vs previews, etc.
The alternative seems to be Feedblitz. Feedblitz isn’t free and as your subscriber base grows it becomes more expensive. Regardless the biggest issue is the lack of control over the email subscribers and the campaign. This is why we set out to build this addon. The key features or reasons why we saw the need for this are: