Looks like everyone stood in their assigned spots.
Here is the 2012 APEC group photo (Putin is in roughly the same position at the Russian APEC meeting, with then Sec of State, Hillary Clinton, in the back row, towards the right):
And the 2011 APEC summit group photo in Hawaii, with Pres Obama front and center:
Looks like Bush got the same treatment in 2008 (back row to the right):
Undoubtedly there is some planning and protocol at play in determining where one stands for such event photos. However, reading too much into such things is pretty silly.
Must be a slow news day...
ADG