I almost forgot, I have two suggestions, too.
1. Add an area on the page where you set your options of what you want to send, etc., for you to type in some text to be included with the message. A textarea thing. So you can add some thoughts or comments, or maybe a promo message, something that you might want to change each time.
2. Right now a user can disable receiving this for himself by editing their options. I'd like to have the same thing in the admin cp part of editing a user, so I can disable it (or enable it

) for a user, myself.
3. (Yes I said two, but this just came to me!) The preview feature doesn't show you exactly what you really end up getting. Could you include a way to send a test email to just one address, like your own address?