Windows Live Messenger is a GUI centric application with much of its unique design breaking away from standard Windows API interfaces. The Messenger development team, to all their credit, have successfully implemented their own, image rich and unique approach to desktop interfaces. Although nothing extraordinary today, it was far more revolutionary several years ago. As revolution turned to evolution, so did Messenger's style. Never have I seen so many changes to a piece of software in such a short timeframe. So below is a screenshot timeline of MSN/ Windows Live Messenger GUI over the past five years (the years of which, I have personally witnessed):


Screenshot timeline: Sign-in Window


Screenshot timeline: Contact List


Screenshot timeline: Conservation Windows