Is there a method to cleanse the newsletter subscriber list. I would like to remove any subscribers that have been sent, and not opened, an email within the past 12 months.

I think it could probably be done using mySQL console?

Alternatively, would it be possible to include a feature in the next release of Newsletter Builder that could identify potentially problematic addresses. Perhaps in the Subscriber Activity Log there could be an option for bouncebacks, rejected, or a list of error codes (in particular 554)?