I wonder if there are any languages or language implementations that he mentioned in this post that weren't ready for real-world use in late 2007 but are ready

I wonder if there are any languages or language implementations that he mentioned in this post that weren't ready for real-world use in late 2007 but are ready now. D has certainly matured since then. How about some more recent languages, like Scala, Clojure, Go, and Rust?