Where is the perfect tool to convert blogs to email?

For this blog and for Brain Food, We are looking for an email service that can convert our blog posts into both daily and weekly mailings. Services like Feedburner can automatically convert each blog post into an email. And a company like Constant Contact (and its many competitors) will take our mailing list and send out mailings.

However, Feedburner won’t let us upload our existing mailing list into their system, no doubt because of anti-spam concerns. And Constant Contact does not have a facility to automatically allow us to convert each blog post into a mailing to our whole list there. We’re currently using Mailman to address this problem, but the problem with Mailman is we are running it locally, and that makes our server liable for spam complaints. Also, Mailman usually puts each blog post into an attachment, instead of into the body of an email.

The ideal service would automatically create a weekly newsletter, including the most recent blog posts. It would also allow easy editing for readability – say, excerpts from the best 3 recent posts and subject links to the rest of them, plus some heading text. The About.com subject guide newsletters are examples of what we’re looking for. It would also include all of the unsubscribe/other reader functionality that Mailman and Constant Contact offer.

Does anyone have a solution to this dilemma? We’re happy to pay for a service that will work for our needs, which are common among blog publishers.