The February 6th, 2015 "Birth of the Green Button" event at SDG&E's Energy Innovation Center featured presentations from utilities and entrepreneurs. It was a big success all around, featuring former White House Deputy Chief Technology Officer Nick Sinai, a video from current Chief Technology Officer Megan Smith (who couldn't be in attendance), Barry Haaser of the newly-formed Green Button Alliance, and utilities SDG&E, PG&E, Southern California Edison, and London Hydro.
DOE has a nice summary here:
For the presentations and technical information on the roll-out of Green Button Connect in California, you can view the presentations here: