Windows Live Messenger has just entered beta (along with several other Windows Live apps). Their beta is important to us because WLM is moving to a new backend for their audio/video support. This new backend is the same one that's already in use by Office Communicator Server. Messenger:Mac users who are using OCS2007 servers can do audio/video chats today -- I've been using it for several months to chat with my (currently snowbound) colleagues in Redmond. WLM using the same backend as OCS brings us here in MacBU one step closer to being able to give users of the personal service the same support for audio/video as can be found in the corporate OCS service.
They're in beta, so they're still ironing out a few things. If you come by the Office booth at MWSF, we'll be giving demos of our support for audio/video on the personal service.