I like the rounded corners for app-icons. But photos, videos and album-covers (music) should have sharp, rectangular corners. Because of 2 reasons: 1. That's the way they also look in normal life, where photos, videos, movie posters and CDs are rectangular and not with rounded corners. So that's more consistent and understandable. 2. That would make it easier to distinguish between apps and photos/videos/music and know what happens when you click an icon.