iPhone a route to Apple’s Tablet?

I’m sure I’m not the only one thinking this, but with the iPhone, Apple is enroute to having the start or one heck of a tablet. Even though the tablet isn’t taking off like it’s promoters would have hoped, the form factor hasn’t died out and recently is becoming quite useful (still needing the pen though). The issue in my mind with many tablets? As soon as they go over the size of a folder – 8.5*11 – they are too big, and any heavier than a kilo, it’s going to get clunky. Ideally, you’d have something that could be about hand sized and fit into a folder (like those old calculators). I think that is what many people who need that form and function for work would absolutely love to have.