I don't know how you do it, but sometimes I comment on a question and get 10 follow-up emails (comments from others), that I do not want.
In other words, I forgot to uncheck "E-mail me if a comment is added after mine."
How I do it for a while already: I find my comment, click on edit, uncheck the e-mail notification.
Would it not be more userfriendly to add a tiny URL in the end of the notification email to let the user unsubscribe per click?