Not sure..VISN does the metro/subways, so I would guess they do the broadcast on these the same as they do the inner city buses.. My guess is the long distance trains that I was referring to would have to do something similar to CCME, but I suppose it could be a replay of network content..
Really though, CCME's is a rebroadcast of network content, right? They just insert there own ads, from what I understand.