UPDATE: sorry guys, guess I got a bit overexcited about this :-) As many readers pointed out, Pete Souza is most likely referring to the Instagram update that enables new image ratios. Pete Souza itself stated this in another post on Instagram.
Pete Souza, the current Chief Official White House photographer for President Barack Obama and the director of the White House Photography Office, and notoriously a Canon shooter, made an interesting post on Instagram, saying:
Trying out the new full frame update and wanted to see how a vertical looked. This is during the President’s round table briefing in New Orleans yesterday. DSLR FYI.
As far as I am informed, Pete Souza is using Canon gear. A “full-frame update” is mentioned. Firmware I guess. The only firmware update for Canon FF DSLR I heard about was for the EOS-1D X.
Thanks for the tip!