This is a great article, Jon; I have to stop and think about these things all the time. How do you feel about the fact that in certain cases, when enough people use a word incorrectly for a long enough period of time, the incorrect usage becomes accepted as correct? I know diehards rail against this.
The transport channel is the bottom-most channel of the WCF stack. The protocols that are typically used in this channel are HTTP, TCP, MSMQ, and named pipes, but WCF allows application developers to use other transports as well, such as Simple Mail Transfer Protocol (SMTP) or File Transfer Protocol (FTP).
Support for the $format Query Option. The OData protocol supports both JavaScript Notation (JSON) and Atom feeds, and OData provides the $format system query option to allow a client to request the format of the response feed. This system query option, if supported by the data service, must override the value of the Accept header of the request. WCF Data Services supports returning both JSON and Atom feeds. However, the default implementation does not support the $format query option and uses only the value of the Accept header to determine the format of the response.