NJ 101.5 FM radio does traffic every 15 minutes, and during rush hour - they break each traffic report into "New Jersey Traffic North" or "New Jersey Traffic South."
It exactly follows our Dunkin' Donuts line, and by now - you probably don't have to be a genius to figure out that NJ 101.5 and Dunkin' Donuts follow the greater media market each NJ county falls into: New York or Philadelphia. But people keep labeling Mercer County either the "Princeton-Trenton metro area" or New York (which wikipedia claims is new as of 2000). I can't seem to prove it . . . but I will say that our line goes through counties . . . and towns!