Install MS CRM 2011 Beta on Windows 2008 SP2 or Windows 2008 R2?

I think everybody is consfuse when choosing the Operating System. So here are the facts:

1. You can choose either Windows 2008 SP2 or Windows 2008 R2.

2. But When usingWindows 2008 R2 you need to consider especially this one:
    Import organization fails with Microsoft Dynamics CRM 4.0 organization database when running on Windows Server 2008 R2.

To work around this issue, install Microsoft Dynamics CRM 2011 Server on a computer that is running the original release of Windows Server 2008, and then try the import organization operation again.