OCS 2007 R2 will be reaching RTM, so I should document the deployment for you. Let me give some brief personal background and then deployment background.
My current title: Senior Program Manager, Early Deployment and Readiness, Microsoft Unified Communications Group.
I have supported the product starting with LCS 2003, 2005 SP1 and OCS 2007 while it was in beta. I came from supporting Exchange all the way back to 4.0 through 2000 and training on 2000 and 2003. This means I remember Exchange 2000 Conferencing! My current role is not a feature PM, one that designs the features for a future release but I am more of a project manager and my current responsibilities are managing Microsoft Consultants that are working with both customers and partners to deploy the product in production. The partners have to deploy the entire product suite and go through a verification call proving that it all works, this is no small undertaking on their part.
My current lab is only 2 virtual machines if you can imagine that. A Windows 2003 Domain Controller running LCS 2005 SP1 and a Windows 2003 member server running OCS 2007. I have images for 2007 CWA and 2007 Edge but rarely are they required for most of my testing. So I will be starting with these 2 images and deploying Windows 2003 x64 and OCS 2007 R2 SE, Mediation Server, Group Chat and Edge roles.
The first thing you need to do – download and install the Best Practice Analyzer. This will alert you to required and suggested fixes for both an LCS 2005 SP1 and OCS 2007 deployment. The BPA requires the administration tools to be installed for providing accurate data for the OCS 2007 and R2 deployment. Here is what I found for my deployment - 3 Important hotfixes missing, 2 on my front end server: 923028, 945055 and 1 for CWA – 945172.
Because the product has not officially reached RTM this is as much information I can share but I will be deploying and recording the experience for you to glean for your labs and proof of concepts.