You all have installed Cumulative Update Rollup 2 (UR2) for OpsMgr 2012, right? If not just follow the steps Kevin described in his blogpost. After installing the UR2 on your agents you want to check if the patches are installed on all your agents.

You can just use the following PowerShell command to have a clear overview of the installed patches sorted by PatchList name.

get-scomagent | sort {[string] $_.PatchList} | select Name, PatchList