Comment by Ingaz

Even more:

1. Common ascendants

Scala is heavily influenced by OCaml and Haskel.

F# is descendant of OCaml, heavily influenced by Haskel.

2. Past

Don Syme designed generics for .NET.

Martin Odersky designed generics for JVM.

3. Erlang influence

Acca - heavily influenced by Erlang and OTP, MailboxProcessor looking quite similar to Erlang processes.

4. Multiple paradigms

Both languages combine FP and imperative. Scala is more OOP, F# is more FP.

And (in my opinion) F# is looking more "clean" than Scala.

Simple thing in F#:

   let (|>) g f = f g

In Scala becames much more complicated. Also I think that discriminated unions are "prettier" than case-classes.