A good friend of mine, who is a real, dyed-in-the-wool, oldschool Microsoft fanatic (it's an amusing quirk to me) still has and uses his.

That said, swarms of Windows Phones does smell funny.

Maybe the OAuth token for a popular WP app got leaked, and now anyone can authenticate with it?

All OAuth tokens, even the official ones, are leaked at this point. Google them.

This! :) :) :)