This is from a reddit ama where the OP has worked through Apollo 1-14. He claims it was Neil in the photo - http://www.reddit.com/r/IAmA/comments/xove1/iama_97_year_old...
I wouldn't rely on that for any real information.
EDIT: Not to mention the fact that the suit says "E Aldrin" on it. I have a hard time believing they swapped suits, too.
It's still hard for me to believe they were passing the camera back and forth. That, with all the other inaccuracies, lead me to believe it's fake. Why someone would purposefully fake that I don't know...
http://www.youtube.com/watch?v=FwZPLfFcYoA&feature
Due to a glitch in the video it's not clear which astronaut is which leading up to the photograph, but if you watch them afterward when they talk through what they're doing, it's clear that Aldrin was the one posing next to the flag.