...and on that question, is there a set release or date for Windows 8 and Office 2013 support?
While the system requirements may be published, they certainly are not linked to any available release. OPA 10.4.3 is still undergoing testing and will be probably be available late April or early May 2013.
UPDATE Release date for OPA 10.4.3 is May 14, 2013
Edited by: Brad Tuckett on 15.May.2013 09:47
There is no set release or date for certified support of OPA on either Windows 8 and Office 2013. This will probably be happening in mid 2013.
OPA 10.4.3 release is now available. Support of Office 2013 and Windows 8 will be supported in an upcoming release.
UPDATE: Support for Microsoft Office 2013 and Microsoft Windows 8 has been included in the OPA 10.4.4 release - see "GA release of Oracle Policy Automation 10.4.4 (+ Connectors + Mobile)"