That's kind of what I imagined. My problem is that I don't want to give my clients any, even limited, control panel access and I don't want to have to enter their announcements into the form myself. I'd prefer that they use the announcement list form mainly because it is Double Opt In. But if the only way they can access that feature is via the control panel I guess it will have to be a discussion list. Is there a good description of that kind of discussion list configuration in the wiki or here in the forum or should I start googling?
It might be worth considering adding an "external" form for people like me. As a web designer It's great to be able to go back to old customers and say, "hey I've got a great new feature you might want to add to your website". It's a good way to drum up a little extra work during these hard economic times.