Given that 50% of the posts talk about skeuomorphism and honestly I didn't know what it was, here's the definition from Wikipedia: "A skeuomorph, or skeuomorphism is when a product imitates design elements functionally necessary in the original product design, but that becomes ornamental in the new product design".
It's a new word for an old concept: a decorative anachronism. Obvious examples from outside the world of computing include stone pillars in front of important buildings, and rivets on jeans.
It's abused here on HN as short-hand for app decorations that people don't like, like the infamous leather treatment on the calendar.
But there are plenty of "skeuomorphic" aspects to iOS that I never see anyone complain about (and sometimes compliment), like inertial scrolling or sliding on/off switches.
