This is a HUGE change from the previous direction. While I think it's going the right way, you can also still see some vestiges of Microsoft not having internalized iOS (and likely Android) design.
One quick/easy example is when you go to the "Recent Documents" in any app, "delete" doesn't have the platform swipe convention. Instead it's hidden under an icon (the one that's usually send/share - NOT an action aggregator).
While I think this is a good direction - I think these details show it's still not a significant priority.
(Disclaimer, I worked on Office Mobile from 2010-2012, but didn't have anything to do with this).
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