C# added "dynamic" keyword in 4.0.
Also, I observe on the docs page this little note that says "As of Scala 2.10, defining direct or indirect subclasses of this trait is only possible if the language feature 'dynamics' is enabled."
Almost all the static languages have some sort of dynamic feature already, and generally have since day one. The mere existence of "dynamic" features isn't my point. The question is, how often are they used, and is the language tending towards more of them or less of them? I don't do Scala, so I can't speak to it, but does every little Scala program use this dynamic package, or is it something rarely reached for, and even perhaps considered a code smell by the community? If it's the latter, then it's not a huge notch in the "dynamic" belt.
I'm discussing the first derivative, not the current state of the world.
def lookup(name: String): Any
myObj.lookup("foo")
myObj.foo
But both of them are about type inference, not dynamic types.
This is not a criticism of the language, simply descriptive of its current position. Go, which is substantially larger at the moment from what I can see, is just barely cracking that boundary that I described, and probably still has a good year or two before it's quite there.
Elixir is currently on a good trajectory, but I would definitely be concerned that trying to be a Ruby on top of the Erlang VM is going to make it a non-trivial challenge to get to the next level of usage, precisely because the Ruby space is covered, covered, and covered again with mature, existing languages. This is, again, not a promise from me it can't succeed, indeed I wish it all the best, just a description of its challenges. It is growing rapidly in its little niche but it may have a serious challenge getting to the next level.
And, back on topic, when this came up on Reddit, I'd observe that Elixir is the only dynamically-typed "up-and-coming" language I can think of. Nim is statically-typed. Rust is static. Go is probably on the way out of "up-and-coming" but it's static.
I also observe that all the dynamic languages are all adding static type support, even when the static type support is inevitably compromised by the dynamic portion of the language. In the meantime, I don't see any static language trying to move in a dynamic direction... in fact, many of the static languages are moving to be even more static! The net flow of feature work right now is strongly in the static direction.