As a followup, I have two question for ESRI or someone who has tested this scenario.
1. Will ArcGIS Server 10.1 sp1 support windows server 2012?
2. Is there an advantage to move my ArcGIS Server 10.1 Virtual Server from windows server 2008 r2 to windows server 2012 or will it perform the same if I keep my VS at Server 2008 r2 under a hyper-v 3.0 environment?