Well, their usage of the the phrase wasn't entirely correct, but close enough for those who don't fully understand the implications of what the DarkNet is. And like you, Jason, I'm surprised they didn't change the name either.
And JustSamantha - yes, CSI Cyber is supposed to deal with those darker parts of the internet crime world. Yes, there really is an internet crime world - DaysDegrassi pointed out Silk Road as one such example. And Silk Road 2.0 - someone else started up another version of it, but the founder of *that* one was arrested too... who knows what's next.