100 years from now, there may be significant medical breakthroughs, particularly regarding nanotechnology. There may also be new forms of entertainment and communication, mainly stemming from holograms. Computers will take up much less space. Imagine something along the lines of projection. There likely will be really cool Eco-friendly buildings and a few new forms of transportation. There may even be a colony in space. Imagine the view!
However, none of this is guaranteed, mind you. What is guaranteed 100 years from now is that the people will be more political than ever. That much I am certain.