In five years I don't think there'll be a reason to have a tablet anymore.
You have to respect all your competitors.
Now if you go exactly where your competitors are, you're dead.
A good browser, apps, good camera, and fast networking in your smartphone is just expected today.
Future is mobile computing - smartphones and tablets are just elements of it. The industry is on the verge of a whole new paradigm.
In five years I don't think there'll be a reason to have a tablet anymore. Maybe a big screen in your workspace, but not a tablet as such. Tablets themselves are not a good business model.