While not as 'language' based as we would like, I do think tremendous progress has been made in language-as-an-interface with the rise of google. It doesn't talk back to me, but I can type a lot of meaningful statements or questions into google and get a 'meaningful' response.
Text/Language search in general is much more useful in the GUI now than it ever was. For instance, I use spotlight for everything - I hardly ever dive into folders looking for something.
