Audiobus’ developers have already pushed an update to the inter-app framework, in advance of Apple’s upcoming operating system:

With iOS 7 just around the corner, we’ve just released an update to the Audiobus app that addresses some issues. We highly recommend updating now to stay compatible with our community of apps.
We’ve been working hard at Audiobus HQ on a significant Audiobus app update (among other things!). Keep your eyes peeled for these in our next update: Audiobus connection presets, multi-channel input device support, and a third thing that we’ll tell you about later on.

Also, without violating any confidential information, it appears that Audiobus will in the future natively integrate with new iOS 7 methods for inter-app routing, meaning that apps that support Audiobus will get support for that OS feature “for free.”

Read the full post on Tumblr, which is the quickest way to get a steady stream of Audiobus updates

As iOS 7 arrives, we should have some more details, as well as the latest on what this means for the (also awesome) JACK for iOS.

Updated: I want to be clear on two points – we’ll know the compatibility situation only as iOS 7 is shipping to the public. And for now, Audiobus will offer compatibility with iOS 7, as in behavior consistent with iOS 6, through updates. They will not initially support new Apple frameworks for inter-app audio. We’ll update you as iOS 7 ships.