Anoop Gupta, the Vice President of the Unified Communications Group at Microsoft gave the Keynote at VoiceCon last week in San Francisco and he was joined by Steve Slattery of Nortel Networks in this talk about the benefits of Unified Communications.
You can view the Keynote video via the VoIP Loop blog, there is a nice demo by Paul Duffy of Microsoft detailing many of the features of the UC solution.