Windows Phone 8 is slick. It's fast moving and information-dense, and it does a fine job of escorting users through their day. Minor annoyances remain, like the lack of a notification center, or the relative weakness of Microsoft's App Store. Many apps you know and love are on Windows Phone, but the selection does not compare well to Apple's juggernaut App Store. The other appeal of Windows Phone is a bit more esoteric. After five years of iPhone and Android dominance, Redmond's OS offers something profoundly different and genuinely compelling.
The other side of that appeal is the continuing reliability and familiarity of iOS. The App Store is massive, the functionality is familiar, and, for many users, it just feels like home. There's nothing wrong with that. iOS 6 is an iterative update to the most intuitive OS on the market. There's a very long and compelling list of reasons that the iPhone is as popular as it is.