Apple Iphone Owner Loyalty declines

For the first time since the Apple iPhone was released in 2007, the number of iPhone owners who say they definitely will or probably will purchase their next phone from the same brand has declined. Although it's not staggering, it is a first. It's striking that European Iphone owners are doubting more than US Iphone users.

http://www.strategyanalytics.com/default.aspx?mod=pressreleaseviewer&a0=5293

Why do you think this is? Is it the price? Supposed lack of innovation. Or is it the desire to try something different? What do you think attributes to this decline the most? And what accounts for the difference between Europe and the US?