Hi, this is my first post in a while... so! yay!
I think your idea is great, it will help promote your website.. which by the way looks awesome since the remodeling!
I do have one idea for your Facebook application: you could have the ranks show on the Facebook profile (noob, supernova, etc.).
Also, just to keep things confidential and safeguard people's identity. A draw back for existing members to add this application would be that maybe they do not want their comments or posts to be read by their friends. Let's be honest, I posted some wild stuff back in the day and I wouldn't really want to go back and delete them so my friends wouldn't see them so I'd just not add the application with my existing BeastToast name. I mean, you have to remember that you would be linking your personal profile with an annonymous profile and your identity would be revealed.
What do you think? I might be over thinking it...