As the title suggests really.
I am flying to NYC in whY?

in October. The flight is on one of the new 777-300 ER's and was wondering if anyone knows what the type of power source the new cabin has?
BA.com assures me that the seats do have power but not the type... I assume the same type as in J, American style plug socket but would like to know for definite.
Thanks to anyone who can help,
J