The nginx 1.9 series has been out since 2015-04-28, including several point updates. It seems to be unavailable even in rawhide right now.
We're using the "stable" branch of NGINX, which is how we've always done things (and is also what all major Linux distributions do). I usually only update rawhide to the "mainline" branch when I'm pretty sure it will become "stable" before or shortly after the next release of Fedora.