"NodeJS / JavaScript / HTML5" - more likely to be just another option to satisfy everyone. I would rather move to Scala than use JS for anything other than rich GUI. Who wants to support business logic implemented in JS by an average developer?
Microsoft would never promote Scala as it's a JVM language. NodeJS is likely given the recent relationship with Red Gate and effort surrounding Azure support.
As for business logic by an average developer - I would say the same thing about every language.
