This is a great resource for those that want to roll their own email infrastructure. We also have some tips about email content in our FAQs: http://documentati

This is a great resource for those that want to roll their own email infrastructure. We also have some tips about email content in our FAQs: http://documentation.mailgun.net/faqs.html#does-the-content-of-my-email-matter-for-deliverability http://documentation.mailgun.net/faqs.html#does-the-content-... The Mailchimp resource mentioned in the OP is also highly recommended reading.