Looks like the Operations Manager team released the Visio 2007 Add-in for System Center Operations Manager 2007 R2. According to their site:
Visio 2007 Add-in for System Center Operations Manager 2007 R2 combines the strengths of two applications widely used in enterprise IT to simplify the creation of customized graphical dashboards showing the health of an environment. Examples of such diagrams include showing objects by geography overlaid on a map, by location in a datacenter or building, by role in a logical view of an application or by topology for complex distributed applications such as Exchange or Active Directory.
For more information see http://blogs.technet.com/momteam/archive/2009/07/31/visio-2007-add-in-for-operations-manager-2007-r2-released.aspx.
J.C. Hornbeck | Manageability Knowledge Engineer