Are there going to be new featuers in Vista that would allow me to pipe audio out of one application directly into another .. sort of like virtual patch cables from the "output" of one app to the "input" of another audio app. 

Many audio production and recording applications use ReWire to accomplish this - each application has to be ReWire aware and the applications act as ReWire hosts or ReWire clients or both.  Will the OS support something like this natively?

Glad to see what I've seen so far.