An Update Rollup 5 (April) is also released for System Center 2012 family. Details can be found at Update Rollup 5 for System Center 2012
You may want to take a look at the link above as it has installation instructions. There is one update for Virtual Machine Manager (KB2824618: A host that is put into maintenance mode does not load-balance virtual machines in a cluster during evacuation. This causes host reserve saturation) and one for operations Manager (KB2831729).
All updates are in Windows Update but if you would like to manually download, below are the links:
- Virtual Machine Manager – (KB2824618): Virtual Machine Manager update
- Operations Manager – (KB2831729): Operations Manager update
For System Center 2012 SP1 Update Rollup 2, please visit: http://www.cdolar.com/2013/04/update-rollup-2-for-system-center-2012-service-pack-1/