Want to know more about UR#2 for SC2012? Go here. For more information about UR#2 for OM12 go here. For a detailed installation guide about installing UR#2 one can use this posting of Kevin Holman (even though it’s about installing UR#1, the procedure is exactly the same).
Even though the RU#2 OM12 KB article states the MPs aren’t updated that isn’t true: These MPBs (Management Pack Bundles) are higher versions:
Every latest RU contains the previous RUs as well, as stated in this posting by the OM12 engineering team: