Absolutely nothing of what he described in that email materialized. And it's no wonder it didn't, since a lot of it is simply wishful thinking. In addition, he didn't address the fact that there are political and not technical reasons behind the absence of certain features (e.g. FFI). They could be done today, without Guile, assuming a consensus on the political front existed.
On the other hand, Emacs Lisp has gotten a lot better and not only knocked out some of the features mentioned by Andy (dynamic modules, native threads) but is also making progress towards new directions (GCCEmacs).
And as I described in my other comment, I completely disagree with his premise that having Emacs be extended in JavaScript, Lua etc would be a plus. The last thing you do with a cohesive ecosystem like Emacs Lisp's is to introduce needless fragmentation that takes away its core strengths.