I just traded up to a Phablet, a cross between a phone and a tablet. A tablet computer is more or less a smart phone, without the phone. And a bigger screen. At the moment, we seem to have some standards in screen size: the standard tablet (10 inches), the mini tablet (7 inches) and the smart phone (from 3 to 4.5 inches). A Phablet is a high end smart phone with a bigger screen, more memory and more CPU power.
The Phablet looks a lot like a smart phone. At the moment, the most popular Phablet is the Galaxy Note II, which is almost identical in appearance to the extremely popular Galaxy III. In terms of shape, features and appearance, you first think... "That's a Galaxy." Then you notice, "That's one BIG phone!" You go from a 4.8" screen to 5.5" That may not sound like much, but that's close to the same size as the original "nook" e-reader from Barnes and Nobel, with a much higher-resolution screen (and more processing power than an entry level PC).
The magic question is, "Who cares?" Well, you do... or you should. Desktop computers made the outsourcing of Knowledge work (KPO) possible. Now, you have all of that power and functionality, plus a camera (scanning, OCR, visual documentation), plus the ability to access the internet from anywhere a Wi-Fi or a cell phone network can be accessed. How many more functions can be automated or outsourced when your PC (and a world of Apps) can fit in your pocket?