Late last month, we published a case study with Syngenta on their deployment of Office Communications Server 2007 to over 21,000 employees.
With 330 offices in more than 90 countries, the challenge described by Daniel Rhein was "Every day, hundreds of our employees collaborate on projects with their colleagues in different locations. Often, these meetings include three or four people, but increasingly we have large projects that require many more people to be involved. We're always looking for ways to make the process more efficient."
Syngenta cites 50% cost-savings over their deployment. The case study provides a good framework for their deployment.