As it says at the bottom of the article, I’d love to hear about command line interfaces that use these things. As far as I know they’re pretty unusual.
If you want to make a command line interface better and it’s written in Python, the easiest and best thing to do is to start using Prompt Toolkit. This post is about reaching for another 10% of functionality after that, but you’ll get the most bang for your buck with that import and 50 lines of integration code. If you want to try it out just install the lastest IPython, which started using it a few weeks ago.