Automattic/jetpack — pull request #1417 by dereksmart (2014-12-15 14:34:07+00:00)
Title: Toggle subscription for new posts.  

Addresses #757

This should be all we need to do on the JP side. Since disrupting Sync is not an option (#), what the plan is here is to send over a boolean to .com as [module_custom_data] and check there before sending out the subscription email.

I've been having trouble testing changes when using my sandbox as Jetpack's API, but I would think we need to put a stop to `send_post()` in subscription-mailer.php