Interesting. 6 years later that’s still a pretty good list. Maybe missing GoLang, today.
First release of Go was done in 2009 according to Wikipedia, that explains why he missed it.
I meant that, today, GoLang would be added to that list.
Great list. Really great list, such diversity (except the inclusion of both PLT Scheme (now Racket) and Clojure). Squeak has been on my list for a while now. Haven’t heard of Io before, will check it out.
What list would you make today?
I would keep it the same mostly. Remove Racket and include Go for sure. Maybe swap Scala with Nirmod.
it’s a foresighted post but they’ve missed the d programming language.  it’s worth checking out as it’s a c / c++ replacement. imagine you are building your application as you wish but with the speed of c or c++. it is used by many system and game developers. it only lacks support for web development as part of stdlib but there’s also a web framework called vibe.d 
there is also a spectacular book on d by ali cehreli.  freely available in english  and turkish .