Now I remember--I think it was the better camera and the larger screen--I use the camera a lot to photograph projects for my crafting blog, so a better camera is a big deal to me. Now I'm wondering how much better it really is! ? Thanks for responding.
There is no "NEED" to upgrade unless the newer version(s) have what you consider "must have" features. I also have a 4S having upgraded from the 3GS. My eligibility for a discounted upgrade is in the May/June timeframe. By that time, I'll likely upgrade to the putative 5S/6 but the 5 isn't as much of an upgrade for me to pay the higher price. BTW, the reported current limitations of the iPhone 5's antenna design with respect to LTE (simultaneous voice/data) is another stumbling block.