Not sure what’s happening lately in the Apple UI design department. Someone over there decided to reposition the window control buttons (you know x,-,+ aka. close,minimize,maximize) vertically in the latest itunes10 (see pics below).

If you prefer the old (proper) way of having them ordered horizontally (see picture above), you can use the commands below:

defaults write com.apple.iTunes full-window -1

If you need to reset it back, you can use the commands below:

defaults write com.apple.iTunes full-window -0