iTunes 9: No Miniplayer w/Green Button!

In theory, if your iTune's window is open, and you click on the green button, it should shrink up into the Miniplayer--this is what it used to do, anyway. But now, if you're in miniplayer, you click on green an open up the window, you're stuck. At least I am. I hit the green button again, and it does not go back to miniplayer. I have to pick that option from under "View" to get the window to shrink.

Am I missing something? Is there some preference or something that I didn't check off--or is this a bug in iTunes 9? "Help" gives me no answers.