[jedimastert]

> I do unsubscribe users if messages start bouncing but I have no way of knowing if they get silently dropped or spamfoldered.

IF you get spamfoldered by enough people the provider will just start sending to the spam folder for everyone. Your newsletter is now useless

[anewone]

And on top of that, some mail providers like Gmail won't even tell you this is happening. I understand why they don't but it's really difficult if you're a small time newsletter trying to get off the ground.