They can call it whatever they want. Whether Im consuming a WCF service from a Delphi SOAP client/WSDL, or via a proxy using a net.tcp binding, the functional end result is the same:
An interface to an remote object.
Quack, Waddle, RPduCk.
>>WCF is just a .NET API for communication.
No. Its a robust framework for persisting a remote interface to, and serializing data between, remote objects via a variety of bindings.
IOW, whatever the M$hills are calling it its just DCOM/OLE/DDE/RPC for the Internet.
I haven't had a chance to look into this specific case, but knowing the history it could either be a completely rewritten communications subsystem, or a WCF call is just a wrapper over the same old DCOM routines. OTOH, from what I've heard the whole TCP/IP stack has been rewritten, so hopefully these got the same treatment.