Aweber is one of the most popular email marketing solutions for bloggers. It lets you send emails, manage subscribers, and offer good tracking. Aside from that you can also send sequence of automatically delivered emails (autoresponder), automatically create emails from your newest blog posts, and target subscribers based on their action, location, etc with a single click. We use Aweber for some of our email lists. Also, you can easily Split Test optin forms template, headlines, headline color, text color, text of submit button, and much more.