> Plus JQuery - I don't see a point in doing it the Scala way when JQuery and other libraries are just as efficent and I will likely use them anyway.

I won't speak about Scala in particular, but using a statically typed language with a strong type system is much more about safety than about "efficiency" (whatever this means). Javascript is brittle, and the idea of doing any kind of refactoring on a large JS codebase is terrifying. Compiling to JS from a more typesafe language makes sense, and you can write bindings for most JS libraries.