During the live letter and media tour interviews, they mentioned they'd tell us more both during the post launch live letter and leading up to 6.1.
I kinda get it, they want all attention on 6.0, and will discuss what's to come after we play the stuff more immediately on our horizon.
But also waiting can be difficult and I'd like a little more info if only so my mind doesn't start taking the mystery of the sanctuaries strange places.