Scala is better than Java (and C#) in almost every way. Even Java 8. I do hope the Scala team updates to JDK 8 and provides platform lambda compatibility. Android is the big problem that pushes everyone for JDK 6 compatibility.
C# has a zillion technical problems, major ugly technical problems, but beyond those, it's not a platform-agnostic, general purpose language. It's an integration langauge for Microsoft tech stacks. If you don't want a Microosft centric tech stack, C# and .NET usually doesn't make sense.