To dovetail upon Starkmojo's comments on inadequate lighting:
inadequate lighting is any lighting equipment that does not help to distinguish the cyclist from the objective visual background of a homo sapien. Our eyes are not perfect and biological shortcuts save on construction costs by assembling an image that is representative not accurate. Night vision is dependent upon contrast and that is what is sorely lacking.
Bike lanes in residential, industrial areas and MUPs are areas where the far background remains relatively dark and this works out fine for even unlit cyclists. Heavy traffic areas and busy retail streets with bright lit ground level signs are the worst at night: our eyes are adapting to dark while the mid and far field is flooded with hundreds of discreet +1,000 lumen automotive and advertising lights.
They are moving and blinking and in to this we toss a ninja or worse, a cyclist that thinks TriMet's or PBOT's 25 lumen - 1 AAA battery light is enough to make them safe.
I don't know about everyone else but I only notice these cyclists in the same manner in which Kirk and Sulu noticed a cloaked Klingon Bird of Prey in Star Trek 3: there is an unexpected background anomaly. All of a sudden you notice that car headlights, which do not normally blink, are blinking in a pattern consistent with a cyclist passing between you and the other car.
I'm not sure how to resolve the need for headlights without making all the roads luminescent.
With better and cheaper LED lighting we could legislate that advertising signs dim at night. Not just to save energy but to reduce the retinal overload that cyclists and more importantly PEDESTRIANS must fight to simply be seen.
Fun facts about how deficient the human eye is: http://xkcd.com/1080/