I am using Pierre Lannoy's simpleNing2MC application to sync my members with MailChimp. I am looking for a way to avoid sending anything from MailChimp to members who have selected "I don't want to receive emails..." on our Ning site. Can I access this property through the API? I don't see anything for mailing preferences.
No, that preference isn't available via the API; it is available though through the member CSV export, so you perhaps you could use that to do an initial cross reference.