It seems they can't go full non-skeuomorphic without looking like a WP rip-off? Finding new symbols for abstract concepts is even harder though, some will stay until we have brain-computer interfaces that will give us new senses.
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.)
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".