Thanks for the kind words and I appreciate you posting this here!
Can you give some explicit examples of when "invoking members on the VM" are a pain? I have seldom found a scenario that I couldn't resolve with an InvokeMethodAction, a blend trigger than can be attached to any UI element and trigger from any
type of event and simply call out to a method. There is a similar one for commands as well. It's just a drag-and-drop behavior in blend and not much more difficult to wire in Cider (the VS2010 editor). Do you have a specific scenario that this wouldn't address?
If you absolutely need to reference the view model in the run time, you can either cast the data context to the VM type when the event you're hooking into occurs, or satisfy imports in the view and use the view model router (you just import it into the view)
to reference it that way.
The shell view is no different than the RootVisual of a Silverlight application, so it would be no different using Jounce or not for aggregate views. For the "concept" you're looking for I think perhaps you want a region that provides the "space"
your component will register to. Then, it's as simple as in the main view model as raising the navigation event for the "shell" items that would go into the regions. Jounce will respond to that event and wire the items in place. There is also a navigation
example in the quick starts that automatically wires navigation buttons based on the exports and then routes to the regions when they are clicked.
There are two types of "publish" style notifications. If the changes are solely UI-based then the Visual State Aggregator can be used to aggregate an event that triggers a state change across controls. If the event involves business logic, every
view model has access to the event aggregator where you can publish and subscribe to global messages and communicate those to the views through data-binding.
I'll be working on a larger reference application using Jounce it's just been busy with Sterling and some other projects but I hope to have it out eventually.