How can I get Nike+ to play songs from Spotify? Recently I've started using the Nike+ app on my iPhone to keep track of the distances and times when I go for a run in the park. I noticed that it has a power songs feature, which I haven't tried out as yet, I imagine it would allow me to specify particular songs that I can listen to while running. 

When I try to use the power songs feature, it only lists the songs that I have in iTunes, I only have a small collection of itunes songs that I would care to listen to whilst running and would prefer to find a way of using the songs that I have on Spotify instead.

I have an unlimited Spotify account so I can store my playlists offline. I am not registered with Nike+.
I'm afraid there isn't a solution currently available for this.  I've been using Nike+ alongside Spotify for over a year now by starting my Spotify playlist then starting a run in Nike+ and selecting "no music". I used to use iTunes playlists which worked with the power song feature and while that was kinda cool it's really not something I miss.

You might email them through their support page (couldn't find a feedback form) and mention it as a feature for future revisions.

http://nikeplus.nike.com/plus/support/#contact