Nice idea to use the gist snippets for code listings! That makes reading the code snippets much more fun!
There’s just one point:
“Switching to another dependency injection framework, then, can be done without modifying every class in the application.”
I highly doubt that and have not seen a large-enough applications where people switched ‘easily’ from one framework to another. This goes for so many frameworks (not limited to DI). Beside that, it’s probably a rather theoretic thing to do.
Either way, a nice write up and a good article!