Con: It's just one more thing to have to keep up with.
You said,
"Furthermore, if one does use a camera, it seems to be more important to have a camera in the rear recording the vehicles behind you, than in the front. Thoughts?"
If the only reason for running the camera is for your own education, then maybe.
Considering that the majority of bike/car accidents are from the front (at intersections/turning) and that around here, license plates are on the rear of the car only.
A rear facing camera would be limited in gathering information that would be beneficial after a crash, even more worthless if the driver didn't stop.