I’ve come a little late on picking up this new up coming premium forum software called xenforo. It is being created by developers who originally played large roles in developing vBulletin who have obviously now moved onto their own projects away from the realms of a company controlling them now (i.e. Internet Brands) who not so long ago acquired vBulletin. I’m interested in the development of this new script as it does look quite polished in its current incarnation.
The demo of it can be seen here:
It looks great utilizing a lot of Facebook-like Ajax/Javascript features, especially with the status updates like in facebook, but conformed onto a forum script. I will certainly be following its development which is likely why I posted it on my blog, for my own benefit. – And as an additional bookmark. 
i’m glad you covered this topic. i was having some trouble grasping the idea.