iTunes 12 MiniPlayer
Chris Johnson (via John Siracusa):
At first, I had no idea how you were supposed to invoke the Mini Player in Yosemite. The first thing I tried was green zoom icon, but that just made iTunes take up the full screen. After clicking on various things in the title bar area, I eventually tried and succeeded with the album artwork. I had mistakenly assumed that clicking the album artwork would give me a larger view of the album artwork.
In the Mini Player, I was similarly confused. Clicking the album artwork made the artwork bigger. Clicking the little double arrow icon was no help, it also makes the album artwork bigger. I’m not sure why Apple decided we needed two ways to see the larger album artwork. The × icon did the trick, but I was afraid to try it, thinking it would quit iTunes.
Update (2014-10-26): Kirk McElhearn:
When you click the close button, the behavior now depends on how you displayed the MiniPlayer. If you displayed it in a way that hid the main iTunes window, closing the MiniPlayer will bring back the iTunes window. If you displayed it and the iTunes window is still visible, then the MiniPlayer window will close, and nothing else will change. In other words, when you close the MiniPlayer, no matter what you do, the main iTunes window will show up again.
