Since a few weeks (2013/2/12) there is SQL Server 2012 SP1 support in ConfigMgr 2012 SP1 available. That way it's not needed to install Cumulative Update (CU) 2 anymore!
We are announcing support changes for the following releases. These changes will be reflected in the Configuration Manager 2007 Supported Configurations and System Center 2012 Configuration Manager Supported Configurations within the next month.
Configuration Manager 2007 and System Center 2012 Configuration Manager Service Pack 1 now support Microsoft SQL Server 2012 SP1.
Source: Support Announcements for February 2013