I have a new Octi arriving in June and very shortly after it arrives I'm of to Austria in it.

The trusty garmin from the old car will be going with us, but does anybody know who the supplier is for the software and mapping in the built in units, and is it possible to plan multi-stop routes ?

From memory the maps are from NAVTEQ, in the current Columbus you can add extra stops. I would imagine the new ones would allow the same.