Yeah, you're definitely right about it being a WCF issue. And it's an error that's not just on the pages section, but on every page of the admin section. I just tried your suggestions, even though I had only one binding (I added a base address prefix) and there still seems to be some issue. I'm thinking there has to be some configuration issue on IIS or in the web.config I'm missing. I'll post more if I find out what's going on. Below is the error in detail straight from the server's event viewer.
Exception: System.ServiceModel.ServiceActivationException: The service '/Sitefinity/Services/Pages/PagesService.svc' cannot be activated due to an exception during compilation. The exception message is: Index was out of range. Must be non-negative and less than the size of the collection.
Parameter name: index. ---> System.ArgumentOutOfRangeException: Index was out of range. Must be non-negative and less than the size of the collection.
Parameter name: index
at System.Collections.Generic.List`1.get_Item(Int32 index)
at System.Collections.ObjectModel.ReadOnlyCollection`1.get_Item(Int32 index)
at System.ServiceModel.Web.WebServiceHost.AddAutomaticWebHttpBindingEndpoints(ServiceHost host, IDictionary`2 implementedContracts, String multipleContractsErrorMessage)
at System.ServiceModel.Channels.CommunicationObject.Open(TimeSpan timeout)
at System.ServiceModel.ServiceHostingEnvironment.HostingManager.ActivateService(String normalizedVirtualPath)
at System.ServiceModel.ServiceHostingEnvironment.HostingManager.EnsureServiceAvailable(String normalizedVirtualPath)
--- End of inner exception stack trace ---
at System.ServiceModel.AsyncResult.End[TAsyncResult](IAsyncResult result)
at System.ServiceModel.Activation.HostedHttpRequestAsyncResult.End(IAsyncResult result)