I copied my IIS 8 metabase (Windows Server 2012) and to an IIS 7.5 (Windows 2008 R2) box. It is working fine. Is there an official statement by Microsoft that confirms that the IIS 8 metabase is backward compatible with IIS 7.5?
We have been running this for a while now without any problems. The only setting that we use and that is not backward compatible is the sslFlags (on configuration/system.applicationHost/sites/site/bindings/binding[protocol="https). So after copying the metabase, we just deleted that attribute and things are fine.