Query the render camera for each render layer

[davus]

Does anyone know a way to query which camera(s) is/are set to render in the render globals. I'm trying to figure out how to query which camera is going to render in each of my render layers. 

So far the best I can do is return a list of all the renderable cameras in the scene, which doesn't really help me if they all aren't set to render. 

Thanks for any help!

-DD