They did, however, create a set of design principles for user interfaces for computer applications (inspired in large part by particular pre-computing graphic design styles, but also including particular principles for providing affordances and feedback for interactive applications within that graphic style.)
Yeah, and iOS isn't following most of them. http://msdn.microsoft.com/en-US/library/windowsphone/design/... I didn't look at every single one, but having used Windows Phone 7&8 for over a year, and scrutinized the released slides from iOS 7, I don't see any place where they are especially similar.
I didn't mean to suggest that it was, I was trying to suggest a better focus for discussions of whether iOS design was following Microsoft in any substantial way than either "flat rectangles", or even "what bits seem generally similar to Win 8".
They did, however, create a set of design principles for user interfaces for computer applications (inspired in large part by particular pre-computing graphic design styles, but also including particular principles for providing affordances and feedback for interactive applications within that graphic style.)