[colin_jack]

"I would also argue that static typing provides a self-documenting benefit that is easy to forget"

Ditto. For me that's by some way the biggest advantage of typing, with refactoring/navigation being the next biggest.

I do wonder if some of these newer languages are going to make the self-documenting aspect even stronger though. I'm speaking here of optional typing and/or implicit implementation (Greeter implements IGreeter if it has the correct methods). For me this will let me put type information and abstractions (interfaces etc) only where they make sense.

Compare that with what you get in current static languages, where projects I've worked on that also use IoC have so many interface-implementation pairs that it becomes difficult to spot the important abstractions.

Interesting times ahead I think.