Ok, so I have implemented my services, created a new WCF service website to host my services in IIS and used svcutil to export metadata to the .xsd and .wsdl files. From these files I generated the service proxy.cs and .config files and added them to the client.
One of my service operations returns a Generic List to the client though. I know how to change the CollectionType of the deserialized DataType by configuring the Service Reference when it has been added from visual studio (Add Service Reference), but how do I change (or set during the creation of the proxy with svcutil(?)) the CollectionType?