I stay with Windows Phone because it works for me; it has the right mix of features, functions, and benefits for my needs. I stay with Windows Phone because I run Windows 8/RT on every machine I have, and it works for me; the UI fits my workflow, the Microsoft account/SkyDrive keeps me in sync, and I like having the same experience on each device.
Plus, I'm a developer and I'm starting to focus on WP development. It wouldn't make sense to develop for WP but not use the platform, heh.