I believe @psychobunny can expand on how NodeBB can be integrated into a WordPress site
A Wordpress commenting system is on the road map, something we're very keen on getting off the ground.
Like Julian said, we're able to customize NodeBB to play along with WP, something we did at http://community.onehundredfreebooks.com
If that's something that you're interested in going for let us know and maybe we can figure out something. 🙂