@nacx The ServiceType should never be configured independently as you have described via the ContextBuilder. The only way to access the CDNApi is through the CloudFilesApi like this:
    CloudFilesApi api = ContextBuilder.newBuilder("rackspace-cloudfiles")
                                .credentials(username, apiKey)
                                .buildApi(CloudFilesApi.class);
    CDNApi cdnApi = api.cdnApiInRegion("DFW");

What else can I do to clarify the intent here?  This is similar to how most of the delegate APIs work today, except it is delegating to a different endpoint.

@zack-shoylev I updated the RegionToCDNEndpoint docs. :)