Here's a link to the webcast. The demo is about 44 minutes in.
And some quotes from the show:
"Xobni - it's actually the word inbox spelled backwards: This is where someone has come into Outlook and decided to add value. "You look over there to the right, that's their unique display area. They help you understand how you communicate, what groups of people you work with."
"In fact, this is really a social networking set of capabilities, but brought into Outlook itself. So we think it's very, very cool to look at mail messages, extract information, they give you statistics about email patterns. It lets you manage relationships. It actually understands the richness of different types of relationships, which is I think the next generation in social networking. Not just one set of friends who all see the same thing, but rather different relationships and the way you connect up and share information."
"This is a great example of having something like Xobni come in and extend things. It lets us see where people want new capabilities in the Outlook-type environment."
Update: A short video clip with Bill's demo is now on YouTube.