Could be that I'm just overlooking something, but isn't that just the default way of doing it? (eg the same way the UMO Dual extrusion kit does it?)
in the video (after a while) there is a small mechanism that somehow lifts the head about 1 or 2 mm and lowers the other one.
it's also the defacto standard way of doing this with 2 nozzles in a static head.. so not that surprising.
It was the lifting part of it I had in mind, and the water cooling, haven't seen that on many machines yet.
Anyhow, I'm really excited to see how Ultimaker has solved this.