Make easy for subscribers to change their email address

In spite of web-based email services and personal domains, email addresses change frequently. If somebody likes your newsletter, they will want to get it at their new address, too. Make this as easy as possible, or you may lose a reader. If your system requires subscribers whose email address changes to unsubscribe the old address by hand and then sign up again with the new address (maybe even being asked nasty questions again), chances are even the most avid reader will wonder whether your newsletter is worth the trouble. So, you should provide subscribers with an easy to way to change their address. The most simple approach is on the page that allows readers to unsubscribe, offer another field where they can subscribe a new address (carrying over all their data) and change the link to that page in the newsletter from unsubscribe to unsubscribe/change address.