My guess is that NDAs probably prevent people from saying, but I'd sure like to see another anonymous developer offer some insight.
Here's the article:
http://discchord.com/blog/2012/6/12/app ... iobus.html
The (currently) last comment states:
Obviously someone hasn't read the release notes carefully enough. There are a couple of new entries under Core Audio.
June 13, 2012 | Unregistered Commenter | Another anonymous iOS developer
While I'm grasping at straws with the whole Audiobus/iOS 6 thing, I must admit that I'm starving for more information on both fronts.
--Sean