ConfigMgr 2012 SP1 SDK has been released on 1/14/2013. Version of this SDK is 5.00.2034.0000 and this SDK release to support System Center 2012 Configuration Manager SP1. You can download it from here.
CM 2012 SDK RTM version has released on 25-June-2012 and I’ve covered that in the post here. However, I’m not able to find any SP1 related information in the updated SDK (I could be wrong because I didn’t do a deep dive). More over, CM 2012 SystemCenterConfigurationManager_SDK.CHM file still pointing to SCCM 2007 Technet articles. For example, If you click on the following link then it will point you to SCCM 2007 Software Update Technet article here.