Microsoft have just announced the availability of Update Rollup 4 (UR4) for System Center 2012 SP1 but there have been some issues with the SCSM component of the update and it had to be pulled back. See this update from Microsoft's Christian Booth:
SCOM and SCVMM both get a number of fixes in this update and it looks like definitely worthwhile rolling out, but you might want to hang on a while and keep an eye out for any gothca's that people might post about over the coming week or two. As is the case with previous UR's, these will start coming down through Windows Update over the next few days, so make sure you're ready for it or at least have it staged for testing through WSUS or ConfigMgr.
Here's a link to the full description for Update Rollup 4 (UR4):
You can also manually download the relevant bits that you're interested in by using the above link.