I use the Windows Messenger, as well as I do ICQ, for my instant messaging needs (if you want my contact, drop me a line).
Playing with some anonymous methods in C# Express on my laptop, I used the good old full screen mode, since my screen can only get as high as 1024×768 and using Visual Studio sucks on resolutions lower than 1280×1024 ever since the 2002 version.
When I went to click on a taskbar button, I noticed something quickly change in my Messenger tray icon. I became suspicious and tried that again.
It appears that our friends at Microsoft decided that they will automatically change your status to Busy, whenever you go and work in fullscreen mode.
Looking for an option to disable this intrusive behavior has been in vain. What gives?