I guess it's safe to announce that we're doing this by implementing a scripting language for jj2. Although coding a new application over something that's already been compiled to binary code is a hidious task, and it may not give you everything you'd expect, but it does open up a lot of new possibilities. It's currently unknown what the final implementation will look like since the whole project is still in very early developmental stage. There's even a chance it might get integrated into jj2+ once it matures.