Sign into Windows Live Messenger and pick a friend you want to watch the video with to open a chat window. An invitation will be sent to your friend when you select ' Messenger TV' from 'activities' list above the chat window. Your friend has to accept the invitation so that you will be able to select, watch and chat about lots of MSN videos.
You can also watch Messenger TV for yourself. To do this, just add Windows Live Agent MessengerTV@live.com as a contact in Messenger and starting a conversation with it. Just saying Hello will invite you to start Messenger TV, accepting the invitation will open Messenger TV.
Messenger TV is recently been made available in 20 countries (Australia, Belgium, Brazil, Canada, Denmark, Germany, Indonesia, Italy, India, Malaysia, Mexico, Netherlands, New Zealand, Norway, Philippines, Russia, Singapore, Spain, Sweden, & the UK). This represents 12 languages (Danish, Dutch, English, French, German, Italian, Norwegian, Polish, Portuguese, Russian, Spanish, & Swedish). Japan and the USA are the two big countries not represented right now.
Messenger TV looks at whatever language you have selected in your web browser, then pulls all of the navigation from http://video.msn.com for that country. In Internet Explorer, you can select Tools, Internet Options to see your Language settings. (Tools > Internet Options >General > Languages button).
For more about Messenger TV, check
UPDATE (12MAY08) : At present here in India, it seems to be unavailable, After accepting the invitation, getting "Windows Live Messenger is currently unable to start this program. Please try again later."
Earlier I had changed the language to en-GB and was provided with UK specific content, even that is not working now.
UPDATE (13MAY08) : Its again working now, Try it ! Select English India (en-IN) to get India specific contents: