You may need to re-download Configuration Manager 2012 and Endpoint Protection 2012 SP1 Binaries!

The binaries for System Center Configuration Manager 2012 and System Center Endpoint Protection 2012 have been updated to correct some minor issues. The binaries have been updated at the Download Center, and also on the Technet and MSDN download sites. For Configuration Manager 2012 SP1, the updated download release of SP1 includes the following hotfix:

Installation error 0x800b0101: System Center 2012 Configuration Manager Service Pack 1 client

http://support.microsoft.com/kb/2801987

MSDN Download Link:

https://msdn.microsoft.com/en-us/subscriptions/securedownloads/hh442898#FileId=52479

Technet Download Link:

https://technet.microsoft.com/en-us/subscriptions/securedownloads/hh442904#FileId=52479

This means if you downloaded the binaries prior to today (1/25) - you will likely need to re-download them or if you already had SP1 installed prior to
January 25, then you can just deploy the above hotfix and be done.

For Endpoint Protection, there are new binaries that include fixed files (Linux/iOS) that were corrupt in the initial release available on the MVLS site.

UPDATE:

The Config Manager Blog has more information and detail here:

http://blogs.technet.com/b/configmgrteam/archive/2013/01/29/announcement-service-pack-1-media-updates.aspx