I’ve never seen any billboard or electronic advertising running on anything running MacOS. The only time I can think macs were used for anything other than the creation of the content was when we used to put Mac minis into broadcasters to deliver the content to. But we put windows on them.
About 10 years ago, I had a job with one of the largest outdoor advertising companies in Times Square, running several huge LED displays, including one that used a camera feed for interactive experiences with the audience.
I don’t know too much about the specifics, but at the time I worked there, all of their screens, including the one that used a camera for AR stuff, were driven by Mac Pro towers running OS X.
So while I can’t say if this is still the case or not, in 2012 many of the times sq billboards were being driven by macs.
