At least in Visual Studio Express 2012 for Web, when creating a Service Reference to a WCF Data Services 5.0.0.0 service with truly RESTful URL (routed properly without the .svc URI or file):
You need to add /$metadata to the service URL to get the metadata
There is an error after downloading/creating the .edmx and .datasvcmap that "Cannot find custom tool 'DataServicesCoreClientGenerator' on this system."
When trying to delete the incomplete Service Reference, an error occurs: "The .svcmap file cannot be found. It may have been moved or deleted. To generate a new .svcmap file, delete the service reference and add it again.". First, I DID just try to delete it, and B, it looks like there is a .datasvcmap file there, not a .svcmap.
Am I missing some tool, or a link to the datasvcutil.exe in VS 2012 Express?
I resolved issues two and three by installing WCF Data Services 5.3.0 RTM Tools.
Hope this helps.