http://blogs.technet.com/jitreddy/archive/2009/02/12/ocs-2007-r2-new-features.aspxWow, What a Technology and Features OCS R2 Offers..... Key new features of Office Communications Server 2007 R2 include the following: Next-Generation Collaboration • Dial-in audioconferencing . Office Communications Server 2007 R2 enables businessesen-USCommunityServer 2.1 SP1 (Build: 61025.2)