Tom Hise wrote:
I'm curious about how the Nikon ML-L3 works. If there were two cameras,
side-by-side, would the remote trigger them both? If not, how does a
camera know if the remote is controlling it or the other camera? Does
anyone have any experience with this?

Are both cameras set to remote control mode? If so, I doubt you could
tell the difference. To do that, you should use something like a Pocket
Wizard set to two different channels on the two cameras.