Hi Mike,
SAP has planned to certify and start with Oracle 12.1.0.2 (which is out since end of July 2014).
Source (page 21): SAP on Oracle Development Update (April 2014)
However 12.1.0.2 is more like a R2 release (in my opinion) based on the functional enhancements / features. The final SAP release/certification schedule depends on discovered bugs, etc. and so the best contact person for a final release date would be Dr. Christian Graf.
Regards
Stefan