Support for Windows 2012 has been introduced on ESXi 5.0 U1, with the following support considerations:
- Installation of patch ESXi500-201209001 (a.k.a. 5.0 Patch 04) is required on ESXi 5.0 U1
- Snapshots, checkpoints and VMotion actions for virtual machines with Windows 8 or Windows Server 2012 are incompatible between hosts running ESXi 5.0 Update 1 or ESXi 5.0 Patch 03 (ESXi500-201207001) with host running later versions of ESXi ( ESXi 5.0 Patch 04, ESXi 5.0 Update 2, ESXi 5.1, etc.). Please refer to KB-2033723 for more information.
- The Guest OS Customization feature in vCenter does not support Windows 8 or Windows Server 2012 in vSphere 5.0.
- Installation instruction can be found here http://partnerweb.vmware.com/GOSIG/Windows_Server_2012.html
For more information about software support, please check the VMware Compatibility Guide