Sounds interesting - I'm still waiting for the car so can't comment on how it works, but the four cars I've driven with satnav - an X Type, a BMW and two Toyota were all different. The BMW puts up a split screen picture approaching junctions which is pretty good, the Toyota does the same but when on a motorway has a split screen with a linear map of the motorway up to three junctions ahead, with distances and a junction map if you're supposed to be leaving the Motorway. To be honest, I can't remember many details of how the Jag system worked other than it put up a split screen display approaching any significant junction.
The Jag system was very quick to recalculate a route, the Toyota almost as quick, but the BMW takes ages to think about if you go of the recommended route, giving plenty of time to get properly lost. The latest BMW systems are a great deal better. The Traffic info on the BMW is superb, absolute crap on the Toyota and wasn't there on the X Type or the first Toyota. The beauty of all of the BMW screen based systems is the "I-Drive" mouse thingy which you can operate easily without having to poke around touching the screen (which I find distracting). I think that I may be underselling the Toyota because my wife's current Toyota satnav has some sort of intermittent fault which can leap to a location 4 or 5 miles away, takes the most devious route it can find (I think that this may be a mismatch between the routing algorithm and the mapping data) and is inconsistent (and sometimes asks us to drive across the central reservation of a dual carriageway). Problem is, I can't get it to malfunction for the dealer so they dismiss it as being simply that I don't understand road preferences etc. This annoys me ! That is an understatement in case you wonder...