Pretty cool. Does the tool process bounces, complaints, and unsubscribes, e.g. auto removes from future mailings?

Have you considered using a hosted platform that uses Amazon SES rather then hosting Sendy or other tools yourself? I own BigMailer and our clients with established SES accounts (high daily rate limits > high limit per sec) see 1m emails go out in a little over 1 hour.

I always wonder why people choose to host email software in house and it seems like the requirement for direct integration with in-house system(s) is one of the biggest considerations when choosing in-house vs. off-the-shelf solution.