I finally got around to getting a smart phone last week. Before friday, I had managed to never commit to android or apple. I was about as confused learning my way around the galaxy S3 as I was the iphone 5; I went with the S3 because I can swap out the storage space, it felt natural in my hands, it was in stock, and the design is similar to my old samsung phone (pre-android touch screen.)
I was a little bummed that android does not support Itunes, since I have a large library that I have been building for years and I like my music; but it took me about five minutes in front of my computer to figure out how to remedy that problem.
If you are invested in a specific eco-system, I really don't see the point of jumping ship... unless the Iphone5 has some major design flaw that has yet to expose itself...