One interesting anecdote: somebody in a financial services
company gave an account of giving D a try as a way to prototype
something quickly, intending to rewrite it later in a more
conventional language. The prototype went straight into
production, and they are happy with it. The C interop was
important for them to have made this possible.
It was interesting, because it is a serious company where people
don't by any means have a hacker mentality, and it was one more
point at variance with the "I am a java programmer but do all my
personal projects in D" narrative, and also because this
particular kind of company is exactly the sort of second wave
early adopter one wants to have.
(I hope I represented this accurately, and tried to make this as
vague as possible whilst still keeping it useful since people
might not want the details of what they do being public).