I don't see that reason yet either, but after playing with a Nokia Lumia I do believe it's within the realm of possibility.
They did get the basics right here, WinMobile is actually surprisingly good. First and foremost it's hands-down the most responsive UI, even an iPhone feels laggy in contrast. Also most of the core interface and features worked really well for me when I tried; the whole thing feels right, the interface is intuitive and beautiful. It seriously makes the iPhone look dated.
What it lacks (apart from bugfixes) is customizability and the app ecosystem. Those are obviously huge issues, but not insurmountable when you have the warchest of a Microsoft.
They did get the basics right here, WinMobile is actually surprisingly good. First and foremost it's hands-down the most responsive UI, even an iPhone feels laggy in contrast. Also most of the core interface and features worked really well for me when I tried; the whole thing feels right, the interface is intuitive and beautiful. It seriously makes the iPhone look dated.
What it lacks (apart from bugfixes) is customizability and the app ecosystem. Those are obviously huge issues, but not insurmountable when you have the warchest of a Microsoft.