I agree. F# and Scala are on the right track. Previous attempts to build total ecosystems around functional languages were too ambitious. In a mixed environment like this they can be allowed to shine doing the things they do best and programmers can ease their way into new paradigms with working code and familiar tools and libraries.
Unfortunately I think Scala is a little too indebted to Java/JVM and tries a little too hard to match the syntactic flexibility of Ruby. A Scala-- would be an easier sell, I think.