At the moment, calls only because the code I copied from did only calls. But I've started fixing it so that it can do texts too.

I have used the VICar sources. vicar uses a caller daemon separate from vicar-telepathy (the CM). My CM follows the same model: qgv-tp is the CM. When it gets a streamed media request, it calls qgvdial to make a phone call.

Not handled. I don't like the idea of polling for texts, nor do I have a defined interface for asking qgvdial for new texts. So the answer right now is also: "Not designed yet". I will look at the google voice plugin for chrome to see what it does to get notifications because it seems to get them almost instantaneously, but thats still some time in the future.

Not desgined yet. Probably tell qgvdial to play it.

The plan is to NEVER pull in Google contacts. There might be a separate contacts app that will sync Google contacts with the n900 contacts. Since I intend to work like vicar, there should be a "Call with qgvdial" button on all n900 contacts.

qgv-tp is a CM shim to qgvdial, just in the way vicar-telepathy is the CM shim to the vicar daemon.
qgvdial can run without the CM; the CM cannot do without qgvdial. qgv-tp is therefore an "addon" to qgvdial. I intend to keep it that way unless there is a compelling reason to do otherwise - primarily because qgvdial is cross platform, but qgv-tp is not.