Michael Faro-Tusino from MyNokiaBlog.com uploaded a video showing the Nokia N9 running the Sailfish OS and he also posted a guide on installing Sailfish OS on your N9.
Remember that this is not the official port so you will experience some bugs such as:
Android layer not working
Swipe down to close, actually being swipe right-to-left
Time not setting properly
Camera and GPS does not work
Apps may need to be launched
twice (crashes first time)