ZAM posted an interview in which Jen Gordy (Lead PvP Designer) talked about spectator mode:
The other thing that became apparent from the arena tournament was just how watchable the matches were. Do you think the game naturally lends itself to that, and is spectator mode something you’re trying to consider?
It definitely does; we just won’t have the resources to accomplish anything useful or the high quality I want to see for launch. So things like spectator modes, shoutcasting support, Twitch.tv support, those are all things that I definitely want to see, but will have to come post-launch.
I would personally love to see a spectator mode for WildStar. It would open up some major opportunities to lead the way for the Strats.co Twitch team for sure.