I can’t speak for Angular, but in Ember this is mostly a shift in terminology. No longer relying on proxying is the biggest change, but all it means is that property paths have to include model. at the beginning—a pretty straightforward modification to make to your code.
Other than that, routable components are just controllers that also have access to their associated DOM element. We’ve spent a lot of time auditing the code in Skylight to prepare for this change, and in almost all cases the modifications necessary are tiny.
When making these design decisions, we looked carefully at our code, and only introduced changes we felt confident we could implement in one sprint. Because of that, I think of the changes in Ember 2.0 as refinements more than tectonic shifts in the programming model.