Not all Apps are available worldwide, and that's decided by the Apps author's. Netflix or Blockbuster, for instance, may not have a program in all countries, and would therefore not release the ability to run their app for specific regions.
I can't speak for any individual app, but they determine which countries get access to their services. If it doesn't show it, it may not be available in your region.
I live in Eu (Denmark) and i bought Samsung plasma Ps50c6505 last mont.I setup wired internet conection on tv and when i open Samsung apps i have just a few apps,like YouTube,Twiter,FaceBook,History,Google maps,and Wether info..everything working great, but i would like to know how can i get other applications like Skype,BlockBuster,Netflix and others..When i click on "Whats new" buton it?s always the same apps..Now can anyone tell me enything about it.THanks to everyone and Cnet forum administration.You are the greatest..!!!