Yeah they don't. It sits outside of the normal series of cards. What I meant was that ideally as a customer you'd have wanted the Titan released at the current rumoured 780 price point as the 780 itself and then the other cards filtering down from that.
Without knowing their R&D costs it's difficult to know whether this was ever a possibility though.
Maybe their R&D costs spent on the Titan helped to reduce the cost of the GTX 780 as the two cards are very similar in design.