A lot of things associated with mpeg manipulation have to be licensed if you have a commercial product, like VRD, so seemingly simple things aren't always so simple. One of the strengths of VideoReDo is it's dependability, so new features are very well developed before they even hit the Beta stage. I think that TVSuite was a major change and new features will be developed for it rather than VRDPlus. If you're going to work with multiple audio streams while editing then the authoring module has to be able to accept them also.
Reading between the lines of what Dan said, I think the authoring will already do multiple audio and/or closed captions.
Users have been clamoring for the editor to support both for quite a while.
Now that authoring has been delivered, I suspect both will be on a short list for future enhancements.
But, that's just one lizard's opinion, so don't go by me.