Intriguing talk, but not very convincing. Running the JVM is a big advantage. But Go will give Scala a run for its money.

Scala definitely. I don't see why it's "better enough" to persist.

Node? Not until or unless you can build a nice fast browser-side GUI in Go. A Go version of GWT that integrated very well with the DOM and supported React-style UI elements would be interesting but nothing like that exists.