I'm in this category. I was expecting to upgrade to the 4S but was underwhelmed. I waited. I was expecting to upgrade to the 5 but I was underwhelmed again. It's not enough of a change to warrant switching.
Since I really want a larger screen (not a stretched 16:9), I'm going to look at the Android options. I bet there are a lot of people doing that. If I can't find one I like there, I will get a cheap 4S just to have the faster processor, Siri, and 3D maps/turn-by-turn. The extra row of icons on the 5 does nothing for me, and the screen is only marginally larger. All the other things are incremental changes that I won't even notice. 18% thinner? Really? Like anyone is going to notice that when it's wrapped in a case.