As you already know, Craft 3 RC became available recently. We have been working hard to update Freeform and Calendar to be compatible with Craft 3. A lot of things changed in Craft 3, and due to the complex nature of our plugins, it has required a great deal of time to convert them. That said, we're excited about the improvements Craft 3 brings, and are looking forward to getting Freeform and Calendar available to you soon!