I hate having the lack of people that I can express my traffic light interests with, anyone know of sites besides this and Highway Divides that I can join. Damn, I really wish they bought back signaltrafficforums
Your thread title is misleading. "Roadgeek related" means much more than just traffic signals, and since you seem to want something you can join and not just read, that should also be made clear.
There are some traffic signal forums on Facebook. I'm in one called "Traffic Signals and Highway Signs," and most of the focus there seems to be on signals. There may be others, but traffic lights aren't really my key area of interest.
A lot of traffic control groups on Facebook also cover traffic lights to a small degree. Signage tends to be a way more popular subject than traffic lights so you might have to work with what you can find.