The context of my question is that Dave posted on his FB a while back which phone he should get, he was on the fence. So I wasn't just being a fanboy asking 'whar is the iPhone, whar???' I knew he was debating it and I was curious what pushed him one way or the other. I would have asked the same had he chose the 4S.
I went GS3 over iPhone simply because I prefer the android operating system. Mostly, I like how I can customize it much more easily than I can iOS.
I'm also a big fan of the large screen.