A few years ago, the local Boston news stations were staggering the newscasts throughout the afternoon and evening, with at least 1 station airing news between 4 PM and 11:30 PM (with the exception of the 7:30-8 PM half hour). Now there's no local news at 8 PM, with WHDH being the only station with news at 9 PM (NECN moved their 9 PM newscast to 10 PM), and ALL FIVE STATIONS (if you count NECN) showing news from 10-11:30 PM.
In my opinion, this market is over-saturated. One of the local news departments is eventually going to fold (I think it'll be Boston 25).