Funny how instead of trying to solve problems, Gnome apps are actually creating new ones, all by themselves, without any outside factor. They must be really bored or something.
All modern desktops have an area called a systray which is a small area where apps that keep running in the background but still provide an interface that is accessed from time to time can be found, usually by displaying their icon here. Such apps are usually music players, instant messaging software, news aggregator, mail clients, etc.. This is useful because the app doesn’t get in the way by being too intrusive. For example you don’t need an instant messenger to take unecessary space when no one is messaging you. Same for a music player, you don’t need it to display anything once you did your music selection and it’s playing.
For these apps, when you press the close button, they go to the systray.. or so you’d think. Because some people think that the close button should be used to close apps, and that for minimizing to systray you should use some obscure keyboard shortcut (ctrl + w, the ‘w’ stands for ‘wankers’) or press the icon in the systray again. Of course, the former behaviour is still available in other apps.
So what happens is that when pressing the close button, some apps will go to the systray and other will just exit. A good example is Rhythmbox which exits when you press the close button. How many users are really running Rhythmbox to play a few seconds then actually quit the app? Probably very very few. How many users said “oh shit” when pressing the same close button? Probably many.
But as usual I bet they’ll spend years and years on that “problem”..