Yeah but now the more irresponsible ones will speed in areas where they know they won't be caught. I don't think it's a legal issue, but an ethics issue; I would feel pretty uneasy doing this. Although I always wanted to implement a mapquest-like image generator - I went as far as downloading GIS files! :) Anyway, sorry for OT.
The idea is to trap these freaks with another trap. No radio show can report all speed traps. Of course the show could mention "Speed traps in L.A.", but who doesn't know that already?