Since i've got kids and a neighborhood full of them, the back-up camera helps quite a bit. I'm old school when it comes to backing-up (survey, get in car, survey again, back-up slowly and keep looking) -- Having the camera is just an added precaution. Although it really shines when backing-up in tight quarters like a cramped parking lot and such. The angle of view is also wider than i can see outside my rear windows when i'm parked between two larger vehicles, so it also helps me "see" oncoming cars when i'm backing out of a spot.
To answer the lighting question, the back-up lights are more than enough to provide illumination up to and slightly over the point of where the camera's field of view ends - even when it's pitch black outside. But, as MovingTarget mentions, YMMV.