MailChimp syncs emails with Privy but does not sync with subscribers from Shopify. Tech support is non-existent. I have been trying to upgrade to a paid account for 48 hours to get any support but MailChimp's automated service is unable to verify the address of our 22,000/sqft warehouse. Will not allow me to add payment information. All my email requests for support just upgrading my payment plan have gone unanswered. A shame but I am forced to look for a different email APP.
MailChimp for Shopify is a free application that connects your Shopify store to your MailChimp account. You can send 12,000 emails to 2,000 subscribers for free each month using MailChimp. For lists of more than 2,000 people, try MailChimp's monthly or pay-as-you-go pricing plans: http://mailchimp.com/pricing/