Discussion lists often require every message to be approved by a moderator before being sent to the rest of the subscribers (moderated lists), although higher-traffic lists typically only moderate messages from new subscribers. Companies sending out promotional newsletters have the option of working with whitelist mail distributors, which agree to standards and high fines from ISPs should any of the opt-in subscribers complain. In exchange for their compliance and agreement to prohibitive fines, the emails sent by whitelisted companies are not blocked by spam filters, which often can reroute these legitimate, non-spam emails.
Take the email below from Paperless Post, for example. I love the header of this email: It provides a clear CTA that includes a sense of urgency. Then, the subheader asks a question that forces recipients to think to themselves, "Wait, when is Mother's Day again? Did I buy Mom a card?" Below this copy, the simple grid design is both easy to scan and quite visually appealing. Each card picture is a CTA in and of itself -- click on any one of them, and you'll be taken to a purchase page.
Dynamic segmentation – As alluded to earlier, you can’t just send out a generic message to everyone on your list. While basic demographic data can be used to segment your list, that’s far from taking the dynamic approach. Automation tools can help you segment your list as they go through the funnel, allowing you to send personalized messaging depending on their actions and behaviors.