I haven’t heard of Feedblitz – just looking at their website now. Appears that they’re a Feedburner replacement specialising in RSS-to-email (sending your blog subscribers an email about latest posts). Their pricing looks a bit steep (considering Feedburner was free) – so I’d probably choose Mailchimp or Aweber over them? That way you can message up to a few thousand people free of charge.
Possibly the most popular option is MailChimp, almost definitely because they offer a free plan for small businesses, and integrate with a multitude of third-party providers. While it lacks some of the most robust features of some of the following platforms, it's very well suited to the needs of smaller teams, startups, and solo workers. This is a no-fuss option, and the paid option is very reasonable at $10/month.
Given the robust features at the planning and execution phases of email campaigns, we had high hopes for MailChimp’s analysis and reporting — and we weren’t disappointed. Reports include all the standard performance indicators, but it also includes analysis pulled from the millions of emails sent through MailChimp. This enables you to see how your campaign stacks up against the industry average, a level of detail that’s rare among free services. Add to that an integration with Google Analytics and an interactive map that shows where in the world your emails are being opened, and you’ve got a service that seems impossibly comprehensive for a free plan.