Nick here from Shopify.
We're no longer supporting adding form action URL's to the footer in the old way. As such, you'll need to use the MailChimp App. This means that when a customer adds their email to the newsletter section, it's pulled into the customer section, and then the app pulls it into your mailchimp listings.
Hope this helps!
Jordan,I think mailchimp only moves new subscribers, to move your existing customer database you will have to export them from shopify and import them to mailchimp (annoying). Also be careful that mailchimp doesnt send them all the welcome email again when you do this (like it did to mine).
Nick, is there a way to tell mailchimp which list to put customers into? previously diffrent sign up foms could be linked to diffrent lists on mailchimp - now it seems all customers are dumped in one place.
Hey Kristen, have you set up an automation in MailChimp to send out an auto email to new subscribers? This is what you'll need for them to receive a welcome email automatically. I can help you with that if you want to email me: firstname.lastname@example.org