One of our friends over on the Office365 team who does a lot of stuff with Orchestrator and PowerShell (and I mean deep stuff), Tim Bertalot, pointed out a cool Visual Studio add-on that lets you visualize the schema of a web service. The tool is called the Open Data Protocol Visualizer and is available on the Visual Studio Gallery here: http://visualstudiogallery.msdn.microsoft.com/f4ac856a-796e-4d78-9a3d-0120d8137722
Once installed, you simply right-click on a service definition inside Visual Studio and select View in Diagram, and the click the Add all link at the bottom.
What you get is a diagram like this that shows you how all the OData entities are related. Cool stuff.
Thanks Tim for sharing that tip!