ARS Technica reports Microsoft accidentally made Windows Live Messenger beta (MSN Messenger 8.0) publicly available:
The beta version, ostensibly called MSN Messenger 8 but referred to in many places as "Windows Live Messenger," has so far been available for use only by invitation. Beta test users could send e-mail invites to their friends, but there was no way for the general public to test the service.
This changed last Friday, when the MSN Messenger fan site www.mess.be posted an "exclusive" story about Microsoft silently opening up the application to all users, turning the program into a public beta. Other sites on the Internet picked up on the story, but it turned out to be simply a glitch on the MSN servers, and not an actual change in company policy. The guilty server was fixed, and the general public was again locked out from the beta, but a posted direct link to the invitation acceptance page may have let the cat out of the bag again.