So just when other OSes (WP7, e.g.) ditch the physical metaphors realism in UI in favor of more minimalistic/reduced graphics style Apple comes in and doubles down.
Personally, to me, it's superfluous, but I can see some people liking it --however, I think it has to eventually retrench.
Yep, Apple is still big on physical metaphors. See iBooks, etc. I'm not a fan. Build a UI that does X as well as possible, not that emulates IRL thing Y that does X.
I think it often serves a real purpose. Shadows and textures are useful for subtly separating foreground and background and bringing relevant content into visual focus.
Sure, but you can use them more effectively if you aren't caught up on making them look like something else. iBooks, for example, has the page crease in the middle, page images around the outside, and goofy animations when you turn the page. It probably helps sell iPads but I think it distracts from what I'm trying to actually do, which is read text. Some day it will look as goofy as the old music player plugins that would add pops and hissing like from a vinyl record player.
I personally think skeuomorphism used well can be a good thing, but it has to be used well. Does the leather texture on Lion's iCal harm the app? IMO, no (though the specific choice of texture and color could be argued with), and I think textures/colors like this can give an app a "face", something to visually distinguish it, and that's important. But the stitching underneath it? It's superfluous, takes up extra space, and adds significant distraction and visual noise. Glad to see it's gone in Mountain Lion.
Likewise, I thought iBooks on iPad looked great at first glance, but over time the extra visuals got annoying and cluttery. I was very happy to see them add Full Screen Mode.
Personally, to me, it's superfluous, but I can see some people liking it --however, I think it has to eventually retrench.