To fire up Messenger TV, users need to start a regular chat session with a friend via Windows Live Messenger, then launch Messenger TV from the list of activities within Messenger. A list of available content from MSN Video will appear, from which a playlist can be created.
The firm hopes the ability to watch clips with friends on different computers will create a new social experience and attract users who already spend hours on social networks.
"Online video has exploded in popularity over the last year, but to date it has been something people watch on their own. Messenger TV is set to change all that," said John Mangelaars, the vice-president, EMEA, of consumer and online for Microsoft.
"Watching video online can now be a social experience, as people watch videos together, make comments and share reactions."
The service will launch in 20 countries including many European countries, New Zealand, Australia, Singapore, Brazil, Canada and Mexico but not the United States.