I recall a thread where they mentioned Tesla was still waiting on the federal government to approve the side door cameras. ...
ISO/FDIS 16505 - Road vehicles -- Ergonomic and performance aspects of Camera Monitor Systems -- Requirements and test procedures
It’s not yet in the US gov’t’s hands. Two month final voting started Oct 1 (Stage: 50.20 (2014-09-29)), ends with November, then (if approved) it will get promulgated into NHTSA's and other's rules. Plenty of time for January.