I'm not sure why, but I've never really gotten used to the ribbon. Especially in Office 2010 , I find it incredibly difficult to navigate and, frankly, hugely annoying. To see it brought to something like explorer is horrifying, especially considering the large amount of vertical space it takes up.

Shouldn't there be more intuitive ways of doing these things? Why is there a need for a move button or copy (one or the other) when you have drag and drop? I know it is very much in vogue to abstract the file system away from the user, and it strikes me that this is exactly the opposite, and just might be just a little over engineered.