@Samie
(I am assuming that when you say, "battery swapping," you mean you pull into a battery swapper - what use to be a gas station - and your depleted battery is swapped for a charged one)
I personally do not see battery swapping as a viable option. With 10+ electric car models in production (or soon to be) with different battery types/locations/makes (passive/active cooling) it would be nearly impossible to get car companies to agree on a specific battery type/placement for future models. The days of 'standardized parts' is gone - which for the most part I hate but this is an area where it might actually be positive.
Maybe once a new battery type is developed which has little deviation - Li-Air or Solid State Battery - maybe then battery swapping can be looked at again; but then all older electric cars are out of luck and the initial price to make nation-wide battery swapping available would be huge for little gain. By this time (8-10 years) everyone will be use to charging in 5-10 mins because by this point fast charging will be in many more places. Heck it'll probably (hopefully) be hard to find shopping centers that don't have 240 volt charging stations for the 3-4 hour charge as you shop.
The only people that would need a battery swapping infrastructure would be freight and long commuters. In this case they'll be stuck with some sort of gas backup, maybe battery swapping for freight (18 wheelers) along highways, or maybe this'll help push a reinvestment in mass transit..... lol a man can dream.


A question for John, or others
Cost reduction in theory points to pure electric vehicles like the Leaf gaining more market penetration compared to the Volt or other types of PEVs. Is this factored into market forecasting? Should government at some point start separating incentives based on the technology of plug-in vehicles?
My opinion is that at a point in the future, pure electric vehicles will cost about the same to produce as ICE vehicles (& we are talking about no government subsides). The only concern I have is that battery swapping schemes will monopolize this market, reducing the producer's desire to enhance battery range & life.