I spent the day working on Listener. The bulk of the work was just cleanup, getting TODO items set up, fixing the setup script, etc. The actual task of voice dictation didn't get moved very far (I got a trivial "correct that") event working, but it doesn't actually make anything happen.
I also started thinking about how to integrate with other applications (and the desktop). That will likely be done via DBUS services, one for the "send keys" virtual-keyboard service and another for the per-session voice-dictation context.