Hi,
In case you see an email address (or other user information) in the subscription form it means you have enabled the setting Display user information if logged in:.
Display user information if logged in: If the user is logged in, the lists he is already subscribed to will be checked by default, and the email (and all other fields) will be already filled in (so the user only has to click a button to subscribe instead of having to fill in the form)
