MOM 2005 with Service Pack 1 now supports all MOM components (Database, Management Server, Console, Agent, Data Warehouse, Web Console, Reporting Console) on Windows Server R2 and above. There is no hotfix or patch required to enable this to work.
I'm not really sure that's much of an accomplishment since Windows Server 2003 R2 is identical to W2K3 SP1 with optional add-in modules. In fact R2 comes as a 2-CD set, the first of which is W2K3 SP1.
What we really need is some R2-based management packs - DFRS, updated AD, etc.
I agree. If we are going to look at the use of R2 we need to be able to monitor it. I would make sense that these updates are released when the Products are released so we can test the whole solution