My take on this is
Car manufacturers always upgrade something-sat nav - front styling- lights- wheels etc etc etc. to entice new buyers or upgraders.
If you 'wait' for the 'next' upgrade you will be waiting forever, or you will have to trade your car in every year to have the latest. Car makers have picked up on how Apple and others now market their products and do these small tweeks to excite new buyers. Unfortunately Cars are somewhat more expensive than Iphones, Ipads and the like.
The current system works well and if you keep your car for more than 3 years it does not matter.
From what I read, the changes are all in the main head unit, so in theory if you have the current 'top' system, the externals should still be there and compatable. You may have to change out the head unit to upgrade. Maybe this is what my dealer meant when he said my system was upgradable.