Using netjack to connect two or more computer running jack is nice. But netjack is compatible only to netjack...
One of the most promising protocols/technologies for the future digital-audio routing is named ravenna which uses only already established protocols to feed audio over IP networks in realtime with a defined latency and sample-phase accuracy. On the long run this should be supported for the jack-audio-connection-kit.
This is a list of features which are stable, inprogress or planned until a certain release.
Features currently worked on for the next release and more or less implemented and working in the developer version from svn:
The Location: A normal room. Well, perhaps not a normal room but a normal practice room filled with lots of musical instruments, keyboards, computers, amplifiers with speakers and such.
The Parties concerned: Several musicians playing different instruments but - sadly - no drummer. The computer will take its place as many times before.
The Occasion: The musicians are gathered for a small jam-session. No well-known songs to play, maybe not even a predefined song structure.