WP7 is under-rated. I've seen more than a few in non-developer hands.
If this is any indication it could imply that people with WP7 are not attached to the platform like iOS or Android users are.
http://www.linuxfordevices.com/images/stories/chitika_androi...
At that point probably close to 70% of all Android phones as measured by website traffic where clearly in the high end (Incredibles, Evo, Droid, Droid X, Droid 2, etc...).
If Android is dominating, it's doing from the top-down.
But I still don't know any non-developers that have one, and only a few of those.