I'm Kim, one of the guys working on this newsletter plugin:
We currently have 60,000 active users, and some of them are often looking for ways to insert their form easily in a bar, or a box, both of which you develop.
Several plugins currently support us. Find a list in this article: http://www.mailpoet.com/improve-your-form/
It's fairly easy to integrate with us. More here:
We would love to see your 2 plugins seamlessly integrated with ours to offer our users more choice, with better solutions.
If you're interested, do contact me via this form: