Questionable Calls Superbowl 43

[3mnkys]

I have a question about the rule on a player landing inbounds after a legal catch...of course I am referring to Holmes catch at the end of the game. I have seen several still photo angles, and from the front, it looks like both feet hit the ground, while from the rear, it looks like the trail foot never hit the ground, and actually landed on the foot that was indeed on the ground. I am simply wanting to know what the definitive NFL rule for the play is...do both feet need to touch the ground, or is one on top of the other good enough. Not trying to start a controversy, because like many big plays, I think the only one who will truly ever know is Holmes himself...Thank you in advance for any replies