If you launch the messaging app and swipe away and relaunch, you will only get 1 window. If you launch the messaging app and open some contacts messages, and then swipe away and relaunch from icon, you will get a new windows. You can keep doing this with as many contacts on N9 to have their message windows open so you can switch between them. I leave the message window open for the people I message often so I can switch to them easily. Edit: I always hoped if the email client also allowed us to do it, but it does not on N9.