title: Has the Mailchimp API changed lately? Wordpress MailChimp Framework suddenly stopped working without modification
body: <p>I had a Wordpress webshop setup, and I am using the Wordpress MailChimp Framework for sending newsletter, among other things. Now, the setup has been running since January 1st, then all of the sudden the Mailchimp framework suddenly stopped sending. The "Everything's Chimpy" ping status does not appear as well, sometimes it's NULL, sometimes it's garbage character.  I am pretty sure I haven't touched any code of the plugin, and a colleague having a totally different project has experienced it as well. </p>
  
  <p>Is any one of you experiencing this as well? I have emailed mailchimp, but as of today they just passed me to another group of theirs, and so far no reply yet. </p>
  
  <p>Also, I remember their reply used to be "text/json", but now I see a reply with Content-type "application/json". I can't find any post regarding these...</p>