You won't even need to change towns. The only reason you will travel is for leveling, and raids (welcome insta raid guild teleport!)
As it is now, players are in 2 cities, Dal + 1 major city for AH. Come cata, you will be in 1 major city and thats it. You will always find somebody in this major city how can craft wathever you want.
In my realm, you either go in Dal or Org, all other cities are dead, now Dal will be dead too. Org will rulz!!!