Apple has a long history of taking the obscure and unproven and popularizing it by taking a chance on new technology and ideas such as the GUI, 3.5" floppy drives, CD-ROMs, wireless networking, track pads, LCDs, wide aspect ratio screens, USB — the list goes on and on. Yes, people have been doing reflections and translucent drop shadows and glossy BS in Photoshop for a long time, but you didn't really see much of it until Apple popularized it and took it mainstream. Now it's freaking everywhere.