Like the Longhorn beta, this test will be using the Connect website using unique invite keys for each person. Although testers that are selected will be able to Invite their friends or family to participate with them.
"The MSN Beta Team would like to invite you to sign up for an upcoming MSN Messenger beta program. During this beta program we will be testing a new version of MSN Messenger.
We are looking for a group of testers willing to actively participate and provide useful feedback to our development teams. This will be a short beta program lasting only about 5 weeks".