I think iPhone users will be split into two groups now.
iOS6 - those who want to get stuff done, simply, easily
iOS7 - people who want the "cutting edge" even if it sucks
Welcome to fragmentation
How about: People who want to have all the benefits of iOS 6 (fast, simple, easy) and wanna have the new UI, new icons, even faster phones and lots of new features, will gladly upgrade to iOS 7. The others, who like moaning and complaining for the sake of it, or those who wanna live in the past will stay on iOS 6.