Supply wagons don't cost command points anymore. They can now give the +10% fire bonus to all units in a city, if you are being assaulted. They prevent the surrender of all units in a city if you are besieged. Depots do the same, but will also gives the fire bonus to all armies in the region, even if the battle is outside.
Militia units in strategic town of their home state, if there is only 1-2 regiments, never goes home in winter (they are at home!). (you can have others units with them)