That makes me wonder if they'd have gotten the same reaction for a successful Windows Phone app (though, for practical reasons, I don't expect many developers to end up testing that).

That's pretty funny, because Microsoft has been actively courting Apple devs. They've had special events featuring Apple devs and companies associated with Apple, making the case for developing on the Windows 8 platform. Including Windows phone, which I suspect Apple and their fanbois aren't too concerned with at the moment.