Ok I'll play. For me it would be pick your poison time. As much as I dislike msft for personal reasons I dislike google and apple even more; so I guess I'd be forced to go with msft for a smartphone. On the other hand I might well go back to a basic handset for voice and text messaging which I could probably live with if I had to.
I'd get something cheap that doesn't require a contract renewal (my carrier would be required to terminate my contract) or use my BB for the meantime (it should mostly work, but no email or most services. Web browsing and hotspot may still work though). Nothing current suits my fancy, but Windows Phone 8 looks intriguing.
I'd probably wind up with an iPhone merely because my Android is not reliable enough to be my primary phone, despite the cool features, and Windows Phone just isn't quite there yet...