I don't fault using incorrect analogies. It's often easier to direct people to an idea from inaccurate but known territory than along a consistently accurate path.
JB: That's amazing. But you did just invest in a company called Vicarious Artificial Intelligence. What is this company?
MUSK: Right. I was also an investor in DeepMind before Google acquired it and Vicarious. Mostly I sort of – it's not from the standpoint of actually trying to make any investment return. It's really, I like to just keep an eye on what's going on with artificial intelligence. I think there is potentially a dangerous outcome there and we need to –
KE: Dangerous? How so?
EM: Potentially, yes. I mean, there have been movies about this, you know, like "Terminator."
KE: Well, yes, but movies are — even if that is the case, what do you do about it? I mean, what dangers do you see that you can actually do something about?
MUSK: I don't know.
....
MUSK: Yeah. I mean, I don’t think — in the movie "Terminator," they didn't create A.I. to — they didn't expect, you know some sort of "Terminator"-like outcome. It is sort of like the "Monty Python" thing: Nobody expects the Spanish inquisition. It’s just — you know, but you have to be careful. Yeah, you want to make sure that —
It seems to me that Musk is trying to point to the idea that AIs may have unexpected dangers, not to any danger in particular.
But Musk starts with mentioning "Terminator". There's plenty of sf literature showing much more accuratly danger of AI, though none of them as widely known as "Terminator".
That AI may have unexpected dangers seems too vague to me, to expect Musk to think along lines of LWers.
http://www.businessinsider.com/musk-on-artificial-intelligence-2014-6
Summary: The only non-Tesla/SpaceX/SolarCity companies that Musk is invested in are DeepMind and Vicarious, due to vague feelings of wanting AI to not unintentionally go Terminator. The best part of the article is the end, where he acknowledges that Mars isn't a get-out-of-jail-free card any more: "KE: Or escape to mars if there is no other option. MUSK: The A.I. will chase us there pretty quickly." Thinking of SpaceX not as a childhood dream, but as one specific arms supplier in the war against existential risks, puts things into perspective for him.