Galaxy S4 thing has a 5" HD display, a processor with up to eight cores, and it even watches you watching it. Just remember that last point while you are perusing your favourite rubber midget lesbian vore collection.
What I hadn't heard of before is the Samsung HomeSync server which is basically a 1TB appliance you put in your home and store all your stuff on, which you can then access from the GS4 or apparently a wide range of other devices. Just don't lose your smartphone..
Of course, the thing with smartphones is that there's always something better just around the corner. The Google / Motorola Xphone that is rumoured could be a GS4 beater.
Anyway.. in the meantime your old smartphone just got a bit more obsolete..