Umm, Scala 3 = Scala "Don Giovani" = Scala 2.14 (backed by Dotty); that's the gist I got from the linked post (thus the DOT calculus reference in this section of the document)

A ways away, but they're spelling it out now: der Dotty cometh ;-)

Sounds like 2018 if the roadmap plays out as planned. Looks tasty, wish it were more like 2016.