Fabrik 3.8 has been released. As usual, we strongly recommend that you backup your site (using Akeeba) before upgrading. Report any issues in the forums, we will answer promptly.
Scheduled task plugins
"System - Fabrik Scheduled Tasks " plugin must be installed and enabled(top)Otherwise you can add scheduled tasks and run them manually from the backend but they won't be triggered automatically.
At the time of writing (Aug 2014) you must get it from GitHub