Laptops or Desktops?

This time I would like to discuss whether laptops or desktops will become more popular as years go by. What will happen in, let us say, 20 or 30 years? Overall, the speed and performance of computers in general is improving a lot each year. The main thing that puts apart laptops from desktops is that they take a lot less space. Since the technology is improving, it is possible to fit better and better components into laptops. Perhaps in 20 or 30 years regular desktops will become a lot smaller than they are right now and there will not be as big difference between desktops or laptops as there is right now. What do you think?