I'd like to contribute to this thread for what it's worth. I'm in Philadelphia. Our networks have their own frequencies for news desk between helicopter. Irrelevant here.
Arguably, as stated, 123.025 is the standard helicopter Unicom in the country and in Philadelphia we consider it a collision avoidance system. Any Chopper entering airspace between Trenton and Delaware announces their existence and intentions. News Choppers never talk on this frequency other than to announce they are there. It's police helicopters, commercial transportation, medivac and news Choppers.
I don't know how well this is known but in my city we always have at least three Choppers orbiting a major event which happens all the time. The Choppers need to talk to each other and coordinate, while orbiting and know each other well and are very experienced Pilots who share everything they have with each other. You'll find more real news on those frequencies than anywhere else.
No matter what city you're in, try 135.8750 as news helo air to air news Chopper frequency 1 and 135.975 as frequency 2.
Hope that helps.