Compared with multi-conversation, Messenger Group is an existing group with each member in, members can talk together at any time without creating a temporary multi-conversation. Messenger Group makes a group of people connecting closer, no matter whether they are on your Messenger contact list. You can create a group for a team, a department or a company to chat online together.
Now if you have a Windows Live ID, then go to Messenger Group website to create your own Messenger Group.
Free to create Messenger Groups
Each Messenger Group can have 900 members at most
Group manager can change group name and display picture
Group manager can set an administrator to help manage group
Group member can change their nickname in the group
At present there are more than three million users and 500,000 Messenger groups have been created.