Martin Taylor, corporate vice president of Windows Live and MSN, said: "Windows Live Messenger offers people the ability to see, talk and share with family and friends in such a seamless way that puts them in control."
"It's built to help people connect and share in all kinds of rich, unique ways," he added.
Windows Live and MSN are set to get a lot of focus from Microsoft. The company intends to commit approximately 1.1 billion dollars (US) of the company's overall 6.2 billion dollar research and development budget to these services.
Good old MSN Messenger, still used by some 40 million people worldwide, will remain active and usable, but you can upgrade to Windows Live Messenger for no extra cost.