Nike changed their website ( http://nikeplus.nike.com/plus/active ) in May 2012:
The site will be down while we move to the new Nike+. Your steps, runs and gym workouts are safe and sound. When Nike+ Active returns, your data will be there -- on a platform that lets you do more than ever before. Thanks for conquering the world with us, and, in the meantime, check out the new Nike+.
But the website is still not available. With my old ipod nano 5g I was able to sync with the new Nike+ website till Spring 2013. My iPod 7G was never be able to sync walks to the website (only the runs). The Nike support told me, that is was a bug, that I was able to sync with the new Nike+ website and now the bug is fixed, so I'm not able to sync anymore.
It looks like, the website will never return, because everyone at apple and nike is telling me, that I'm the only guy, who is using the ipod for stepcount.
regards harry