Add option for email format

Recently, MailChimp has started to provide email templates that are optimized for mobile delivery.

After testing these myself, I can see that there is a clear advantage reading these on a mobile device and can imagine a better response rate because of it.

That said, it would be great if we could have some things built into the integration that would allow a user to not only opt in and out of lists, but also, for each list they've opted in for, be able to select their preference for receipt of those emails....desktop or mobile. Then we'd need a way in our MailChimp list to ensure that these "tags" are utilized when sending out emails, using the appropriate template for each user.

Hope that helps explain....please let me know if there's anything else I can provide.

Thanks for your consideration.